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IntoScience TEACHER RESOURCES & INFORMATION GUIDE

TEACHING THE AUSTRALIAN CURRICULUM WITH INTOSCIENCE:

CHEMICAL SCIENCES - YEARS 7 & 8

IntoScience www.intoscience.com | [email protected] | 1300 850 331 | © 3P Learning

Foreword Welcome to IntoScience and thank you for joining us on this journey of discovery. I hope you find this resource book useful and relevant to you and your students. I am confident that using IntoScience with your students will be extremely rewarding. How students learn, and therefore how we teach is an ever-evolving process. The teaching of critical thinking skills and higher-order thinking are becoming more prevalent in today’s modern classroom. Skills such as these are invaluable to the scientific process and in developing scientific thinkers. Couple this with the exponential progression and access to technology, the classroom of today is a vastly different landscape even when compared to just the last five years. Inquiry-based learning, and by that I mean the approach to learning which involves the investigation and exploration of problems or questions, is something every science teacher does through practical activities and experiments. Giving students problems, often with guidance, and letting them formulate questions, test hypotheses, record results and draw conclusions is the very essence of science and totally encapsulates inquiry-based learning. However, when it comes to teaching the theory side of science, the inquiry-based model is often lost. In many cases, this is due to not having the tools or resources to allow teaching and learning in an inquiry-based way. This is exactly where IntoScience becomes an essential part of the teaching and learning process. From ‘doing’ mitosis to crashing cars when investigating friction, to playing basketball on the moon, IntoScience brings to life theories and concepts in a way in which no other resource can. It immerses students in a world of science, giving them the skills to grow as budding scientists. It brings scientific theories to life by questioning, doing, interacting and observing whilst staying true to the principles of science. Having taught science for 11 years, I am very proud to be a part of the IntoScience team and to have the opportunity to truly enrich students’ lives. My aim as a teacher, and our aim at IntoScience is to inspire students to love science and to apply a scientific world view in their lives, which I am convinced is essential in today’s modern world. Seeing the way students respond to the program, how they love exploring and finding things out, and above all, how much they love learning science, is the most satisfying feeling you can have as a teacher. I wish you well in your teaching of science and I am confident that IntoScience will help enrich your science teaching experience. Welcome to the future of education, and thank you for embarking on this incredible journey with us. I hope you thoroughly enjoy it.

Dave Canavan MSc QTS Dave completed his Biology Degree with Qualified Teacher Status in Manchester, where he taught High School science while completing his MSc in Behavioural Ecology. Dave then emigrated to Australia where he became the Head of Science in a government school which saw record numbers complete a science at Year 12 for that school. Dave then spent 5 years teaching science and eventually becoming the Principal of a British International School in Thailand where all students of varying ethnicities all achieved a grade C and above for their science IGCSE qualification during Dave’s time at the school. He now works to implement IntoScience in schools across Australia, the UK and the USA, changing one classroom at a time and bringing the teaching and learning of science into the future.

IntoScience www.intoscience.com | [email protected] | 1300 850 331 | © 3P Learning

Catering to your style We all have different teaching styles but whatever your style, IntoScience can cater for you. IntoScience can be applied in many different ways, and different activities lend themselves to different styles of teaching and learning. Here are a few different ways in which you may want to use the program: Flipping the Classroom What is it? – It is where students come to a new topic with some prior learning (generally as homework) from which you can then consolidate and build upon. IntoScience example: – The Characteristics of living things activity in the Cells topic runs through the seven habits of all living things. The students could complete the activity at home achieving all seven inquiry points. Then in the first Cells topic you can bring up the activity on the projector or IWB and run through the activity to consolidate the concepts and alleviate any misconceptions. Benefits? – It provides a great introduction to a topic, promotes class discussion from the outset and also provides a platform from which to build instead of starting from scratch. Independent Learning What is it? – Working and learning with minimal instruction and guidance. IntoScience example: – In the Elements, compounds and mixtures topic, the Properties and uses of elements activity lets students explore and test the properties of elements. Whilst students are independently learning, you can walk around and help those who require it or have them explain to you what they are doing, thereby demonstrating their understanding. Benefits? – When students are ‘doing’ as opposed to listening or taking notes, they discover, learn and understand more. Guided Teaching What is it? – A mixture of guided teaching and independent learning. IntoScience example: – The Particle matters activity in the States of matter topic is structured so that on each screen within the activity there are things to do and explore for the students, and to have that explained and consolidated by the teacher at each step should ensure a thorough understanding of the concepts. Benefits? – Sometimes it is helpful to have a concept projected at the front of the class, explain the science behind it and then let the students explore, before moving onto the next area. Formal Assessment What is it? – An assessment of understanding resulting in a grade reflecting their understanding. IntoScience example: – The Mid and End Challenges contain curriculum-based questions from each topic. Mid Challenges contain a set of 10 randomised questions and the End Challenges contain 20 randomised questions. In the Teacher Controls menu, you can access the Teacher console to see the results of each student and if necessary, have them repeat the test knowing that the questions won’t be exactly the same. Benefits? – A great way to gauge a student’s understanding of the concepts. Higher Order Thinking What is it? – This is where problems require students to think critically, applying logic and creativity in order to solve problems. IntoScience example: – There are many text-entry areas in IntoScience where truly deep thinking can be demonstrated and assessed. In the Taxonomic ranks activity from the Classification of organisms topic, towards the end of the activity it asks students to choose one of the four models which they think best represents the classification hierarchy model. It then asks the students to explain the strengths and

IntoScience www.intoscience.com | [email protected] | 1300 850 331 | © 3P Learning

Catering to your style weaknesses of this model in their own words. As a teacher, you can go into those text fields and view all of your students’ answers. You can choose to discuss these with the class or individually. This allows you to gain an understanding of how well your students grasped the concepts. Benefits? – Developing these skills is the true making of a budding scientist. Not only can you as a teacher really glean whether the students understood a concept but you can also alleviate any misconceptions if and when they arise. Homework What is it? – Work completed outside school hours, generally for consolidating understanding. IntoScience example: – Any activity can be undertaken by the students outside of the classroom, provided they have a suitable device and Internet connection. As IntoScience is multi-platform, and as work completed at school on one device is saved to the cloud, the students can simply log onto another device and continue working. Inquiry points can be seen in the View class results area, allowing you to check whether a student has done their homework or not. Benefits? – If a student was given the choice to complete an IntoScience activity or work from a textbook for homework, IntoScience wins everytime! Exam Preparation What is it? – The necessary revision process undertaken by students before exams. IntoScience example: – As IntoScience is broken down into topic areas, students can select the relevant topic area and work through all of the activities and Mid and End Challenges, thereby ensuring complete curriculum coverage for the topic in a fun and engaging way. Benefits? – As each activity is a unique learning space, the students will have an anchor point from which to remember the concept. For example, if revising heat transfer methods, the camp fire scene used in the Conduction, convection and radiation activity is a great way to remember the concepts. Explicit Teaching What is it? – The classic ‘chalk and talk’, where a teacher is explaining a concept to all of the students in the class, generally from the front of the room. IntoScience example: – Many activities are suitable for presenting directly to the class. There are also tools and simulations you can use as a reference whilst teaching, for example, the periodic table (accessed from the tools button on the top menu bar) allows you to select individual elements and read about their properties, or select groups, periods or filter between metals and non-metals, AMU and more. Benefits? – Instead of having to trawl the net for suitable diagrams, simulations or videos, IntoScience has them all embedded within the program which you can find using the search function on the top tool bar. Group Work What is it? – Students collaborating, sharing ideas and discussing concepts in order to reinforce understanding. IntoScience Example: – Students often gain a deeper understanding of concepts when working in groups, so wherever there are extended answer sections, it may be a good idea to have students discuss the answers in pairs or groups. They can then input their own answers using their own account. Benefits? – When students talk to each other, they teach each other. The discussions taking place can often encourage deeper understanding.

IntoScience www.intoscience.com | [email protected] | 1300 850 331 | © 3P Learning

How to use this guide This resource set has been created in four sections to reflect the four areas of science according to the Australian Curriculum: Biological sciences, Chemical sciences, Physical sciences and Earth and space sciences. The books are broken down into individual topic areas within each science. They are then further broken down into the activities within each topic related to the specific curriculum elaborations. After the curriculum elaborations, you will find lesson guides for each of the IntoScience activities, followed by worksheets and worksheet answers. Below is a suggested pathway for using IntoScience, which includes pre-lesson preparation followed by a guide for when the lesson commences. Pre-lesson preparation •

Open the relevant science manual and turn to the topic which you are teaching. Ensure the curriculum elaborations match what you are covering and then open to the appropriate lesson guide.



Familiarise yourself with the Summary of Key Learning Points at the top of the lesson guide and glance over the talking points and extension ideas.



Sign in to IntoScience on your device and click on Activities in the top left-hand corner.



Find the topic you are teaching and click on it to see a list of the activities within the topic. Select the activity you would like to use.



Work through the activity whilst referring to the lesson guide (by selecting the L on the bottom left of the screen) taking note of where the students will achieve their inquiry points and review the suggested completion levels to see how it will relate to your students.



Print the worksheets to use as a supplementary resource, for advanced students or to use for homework.

During the lesson •

When the lesson begins, have the students sign in with their individual Usernames and Passwords. On your device, open the activity you want to teach and select the settings button in the top right-hand corner.



Check you have selected the correct class in your teacher controls menu. Select Summon class. This will bring all of the students to the activity you want to teach from, restricting their navigation.



Once the students have completed the activity and earned their inquiry points, you can release them by turning off Restrict navigation in your Teacher Controls menu.



If there is time, a nice way to finish a lesson is to encourage the students to explore the quests or challenge each other in the interactive science quiz: The 3rd Degree.

IntoScience www.intoscience.com | [email protected] | 1300 850 331 | © 3P Learning

Index

VOLUME 2: CHEMICAL SCIENCES LESSON GUIDE

WORKSHEET

ANSWER SHEET

Activity: Recognising pure substances from mixtures

11

-

-

ACSSU113

7

Activity: What makes a mixture?

12

-

-

ACSSU113

7

Activity: Examples of pure substances and mixtures

13

-

-

ACSSU113

7

TOPIC

CURRICULUM YEAR CODE

PURE SUBSTANCES AND MIXTURES

Activity: Stir it up! Mixtures that are solutions

14

-

-

ACSSU113

7

Activity: Solute + Solvent = Solution

15

16

19

ACSSU113

7

Activity: What is a suspension?

20

-

-

ACSSU113

7

Activity: Physical properties of a substance

24

26

28

ACSSU113

7

Activity: Filtration and evaporation

30

-

-

ACSSU113

7

Activity: Distillation

31

-

-

ACSSU113

7

Activity: Filtration: Save the fish!

32

-

-

ACSSU113

7

Activity: Exploring more separation techniques

33

-

-

ACSSU113

7

Activity: The island activity

35

-

-

ACSSU113

7

39

42

45

ACSSU152

8

Activity: Changing models of the atom

48

50

55

ACSSU152

8

Activity: Structure of the atom

60

62

66

ACSSU152

8

Activity: Introduction to the periodic table

70

73

76

ACSSU152

8

Activity: Properties and uses of elements

79

81

83

ACSSU152

8

Activity: Comparing compounds

85

87

89

ACSSU152

8

Activity: Naming compounds

91

93

95

ACSSU152

8

Activity: Physical and chemical changes

100

102

104

ACSSU225

8

Activity: Signs of chemical change

106

108

110

ACSSU225

8

Activity: Types of chemical reactions

112

115

118

ACSSU225

8

Activity: Law of conservation of mass

121

123

125

ACSSU225

8

Activity: Particle matters

132

135

137

ACSSU151

8

Activity: Compressing matter

139

-

-

ACSSU151

8

Activity: Changing states

141

-

-

ACSSU151

8

Activity: Diffusion in the lab

144

-

-

ACSSU151

8

Activity: Expansion Experiments

146

148

149

ACSSU151

8

Activity: The Particle Model Examiner

150

152

154

ACSSU151

8

Activity: Using models in science

156

-

-

ACSSU151

8

TECHNIQUES FOR SEPARATING MIXTURES

ELEMENTS, COMPOUNDS AND MIXTURES Activity: Classification of matter

CHEMICAL REACTIONS

STATES OF MATTER

VOLUME 1: BIOLOGICAL SCIENCES VOLUME 2: CHEMICAL SCIENCES VOLUME 3: EARTH AND SPACE SCIENCES VOLUME 4: PHYSICAL SCIENCES IntoScience www.intoscience.com | [email protected] | 1300 850 331 | © 3P Learning

CHEMICAL SCIENCES

© 3P Learning

CHEMICAL SCIENCES

© 3P Learning

PURE SUBSTANCES AND MIXTURES

9

TOPIC SUMMARY: IntoScience topic: Pure substances & mixtures Identify pure substances from mixtures and delve into solutions and suspensions.

Description: Mixtures, including solutions, contain a combination of pure substances that can be separated using a range of techniques [ACSSU113] ACTIVITY: RECOGNISING PURE SUBSTANCES FROM MIXTURES Understand the differences between pure substances and mixtures. Explore examples and ways of grouping mixtures. Elaboration: recognising the differences between pure substances and mixtures and identifying examples of each [ACSSU113-1] Inquiry skills: Questioning and Predicting • Summarise data, from student’s own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS130] • Referring to relevant evidence when presenting conclusions drawn from an investigation [ACSIS130-4] ACTIVITY: WHAT MAKES A MIXTURE? Investigate the distinct properties of mixtures and their unchanging components. Elaboration: recognising the differences between pure substances and mixtures and identifying examples of each [ACSSU113-1] Inquiry skills: Planning and Conducting • Collaboratively and individually plan and conduct a range of investigation types, including fieldwork and experiments, ensuring safety and ethical guidelines are followed [ACSIS125] • Developing strategies and techniques for effective research using secondary sources, including use of the internet [ACSIS125-4] Communicating • Communicate ideas, findings and solutions to problems using scientific language and representations using digital technologies as appropriate [ACSIS133] • Presenting the outcomes of research using effective forms of representation of data or ideas and scientific language that is appropriate for the target audience [ACSIS133-1] • Using digital technologies to access information and to communicate and collaborate with others on and off site [ACSIS133-2] General capabilities: Literacy, Critical and Creative Thinking ACTIVITY: EXAMPLES OF PURE SUBSTANCES AND MIXTURES Decide whether each of these items are examples of pure substances or mixtures, and sort them out. Elaboration: recognising the differences between pure substances and mixtures and identifying examples of each [ACSSU113-1] Inquiry skills: Processing and Analysing Data and Information • Summarise data from student’s own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS130] • Discussing investigation methods with others to share ideas about the quality of the inquiry process [ACSIS130-1] General capabilities: Critical and Creative Thinking © 3P Learning

10

TOPIC SUMMARY:

PURE SUBSTANCES AND MIXTURES

ACTIVITY: STIR IT UP! MIXTURES THAT ARE SOLUTIONS Some mixtures can be classed as solutions. Which of these do you think are solutions? Elaboration: identifying the solvent and solute in solutions [ACSSU113-2] Inquiry skills: Processing and Analysing Data and Information • Summarise data, from student’s own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS130] • Comparing and contrasting data from a number of sources in order to create a summary of collected data [ACSIS130-2] • Referring to relevant evidence when presenting conclusions drawn from an investigation [ACSIS130-4] ACTIVITY: SOLUTE + SOLVENT = SOLUTION Identify solutions and work out which components are the solutes and which are the solvents. Elaboration: identifying the solvent and solute in solutions [ACSSU113-2] Inquiry skills: Questioning and Predicting • Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge [ACSIS124] • Using information and knowledge from previous investigations to predict the expected results from an investigation [ACSIS124-3] Processing and Analysing Data and Information • Summarise data, from student’s own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS130] • Identifying data which provides evidence to support or negate the hypothesis under investigation [ACSIS130-3] General capabilities: Literacy, Critical and Creative Thinking ACTIVITY: WHAT IS A SUSPENSION? Explore the fact that suspensions are a different type of mixture where particles are suspended. Elaboration: identifying the solvent and solute in solutions [ACSSU113-2] Inquiry skills: Questioning and Predicting • Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge [ACSIS124] • Using information and knowledge from previous investigations to predict the expected results from an investigation [ACSIS124-3] Processing and Analysing Data and Information • Summarise data, from student’s own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS130] • Referring to relevant evidence when presenting conclusions drawn from an investigation [ACSIS130-4] General capabilities: Critical and Creative Thinking

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11

RECOGNISING PURE SUBSTANCES FROM MIXTURES

LESSON GUIDE

Students explore the differences between pure substances and mixtures, comparing different states of matter and their properties. Suggested time: 10 minutes Summary of key learning points Students: - recognise the differences between pure substances and mixtures - recognise common liquids and gases as mixtures - identify an alloy as a mixture and recognise its properties RECOGNISING PURE SUBSTANCES FROM MIXTURES 5 minutes This page introduces students to the definitions of pure substances and mixtures. They can then explore the items by selecting them to learn more about them. Selecting all items = Inquiry point 1 Extra activity: Get students to list pure substances and mixtures in the classroom around them. SCIENCE EXTRA: ALLOYS 5 minutes Alloys are interesting mixtures as their properties are often somewhat different from the elements they are made from. Brass (copper and zinc), steel (iron and carbon) and bronze (copper and tin) are all common alloys. Extra activity: Students could research the properties of the alloys brass, steel and bronze and research one more alloy and describe its properties and uses. Other common examples of alloys are: pewter (used for making trophies), amalgam (used for dental fillings), rose and white gold (and yellow gold for jewellery) and solder. Students answer a question about the benefits of alloys. Suggested answer: (Inquiry point 2) Alloys can combine the best properties of elements. For example, 9 carat gold has gold for its appearance and lack of reactivity, but includes metals like copper and nickel to make it harder and more durable. Suggested completion levels Basic - Inquiry point goal = 1 Students at this level will: define the terms 'pure substance' and 'mixture'. Core - Inquiry point goal = 2 Students at this level will: explain how a pure substance is different from a mixture, using examples from everyday life. Advanced - Inquiry point goal = 2 Students at this level will: describe the similarities and differences between pure substances and mixtures; identify examples of pure substances and mixtures, listing their major components; assess the importance of man-made pure substances and mixtures to everyday life.

PURE SUBSTANCES AND MIXTURES © 3P Learning

12

LESSON GUIDE

WHAT MAKES A MIXTURE?

Students identify the properties of mixtures and recognise that the properties of the constituents do not change when the mixture is formed. Suggested time: 15 minutes Summary of Key Learning Points Students: - identify the properties of mixtures IDENTIFY THE PROPERTIES OF MIXTURES 15 minutes Mixtures are different from both pure substances and compounds in that they: - can easily be separated into their constituents through physical means - do not involve a chemical reaction - have the properties of their constituent substances - are not combined in a fixed proportion Students are introduced to an alloy (yellow gold, which is used in jewellery making and which is a copper and gold mixture) and are asked to consider why an alloy might be used and what elements are mixed with gold to make jewellery. White gold: usually nickel and gold Rose gold: copper and gold (a higher proportion of copper than yellow gold) Students then look at mixtures of water and sand and salt and pepper to see that mixtures are: - not in fixed proportions - maintain the same properties of the substances that are mixed together Students are then asked to consider that sodium hydroxide solution is a mixture as it has no fixed proportions and the properties of both the water and the sodium hydroxide are unchanged. Science Extra: A closer look at mixtures reveals that they can be made up of elements or compounds or combinations of the two.

PURE SUBSTANCES AND MIXTURES © 3P Learning

13

EXAMPLES OF PURE SUBSTANCES AND MIXTURES

LESSON GUIDE

Students understand the differences between pure substances and mixtures, and identify examples of each. Suggested time: 15 minutes Summary of Key Learning Points Students: - understand that pure substances are composed of one type of element or one type of compound - understand that mixtures are composed of two or more types of elements or compounds - accurately identify the pure substances and the mixtures in a line-up of substances Extension activity: Create a table of pure substances and mixtures. (additional 15 minutes) UNDERSTAND THAT PURE SUBSTANCES ARE COMPOSED OF ONE TYPE OF ELEMENT OR ONE TYPE OF COMPOUND 5 minutes Students read a definition of a pure substance and see a number of examples. A pure substance is just one type of element or compound on its own. UNDERSTAND THAT MIXTURES ARE COMPOSED OF TWO OR MORE TYPES OF ELEMENTS OR COMPOUNDS 5 minutes Students read a definition of a mixture and see a number of examples. A mixture is made up of two or more elements or compounds. DIFFERENTIATE BETWEEN PURE SUBSTANCES AND MIXTURES 5 minutes Students identify the pure substances and the mixtures in a line-up of substances. Identify 10 or more substances in the classroom or home and create a table of pure substances and mixtures. (Additional 15 minutes)

PURE SUBSTANCES AND MIXTURES © 3P Learning

14

LESSON GUIDE

STIR IT UP! MIXTURES THAT ARE SOLUTIONS

This activity expands on the differences between solutions and suspensions. Students watch a video and make their own observations. Suggested time: 15 minutes Summary of Key Learning Points Students: - observe the difference between suspensions and solutions - understand the process by which a solute dissolves in a solvent OBSERVE THE DIFFERENCE BETWEEN SUSPENSIONS AND SOLUTIONS 15 minutes Students watch a video that shows four different substances being stirred into four separate glasses of water. Students are asked to record their observations for each glass of water. Soil - does not dissolve in water and remains suspended in the glass of water, settling to the bottom of the glass. Sugar - appears to dissolve in the water. It disappears from view. Oil - appears to be mixed in the water, but then settles on top as the stirring slows. Coffee powder - appears to dissolve in the water, changing the colour of the water. Students are also introduced to the concept of a solvent and a solute in a solution. The water being the solvent, and the sugar being the solute. UNDERSTAND THE PROCESS BY WHICH A SOLUTE DISSOLVES IN A SOLVENT Students see that, when a solute dissolves in a solvent, the particles are completely spread throughout the solution and invisible to the naked eye. Students watch a video illustrating that light rays can pass straight through the solution. Conversely, light rays would not pass directly through a suspension. The question is posed: why does salt water dissolve in water sometimes, but at other times makes the water cloudy? (The water appears cloudy when it becomes saturated with salt.) Students understand that solutions cannot be filtered. They are asked whether solute residue would be visible on filter paper. (The answer is 'no' because the solute particles are so small, they would pass directly through.)

PURE SUBSTANCES AND MIXTURES © 3P Learning

15

SOLUTE + SOLVENT = SOLUTION

LESSON GUIDE

Solutions are mixtures and have certain characteristics. Solutions are composed of a solute and a solvent. In this activity familiar solutions are explored. Suggested time: 30 minutes Summary of Key Learning Points Students: - describe the characteristics of a solution - identify mixtures as solutions or not solutions - label the solute and solvent in known solutions DESCRIBE THE CHARACTERISTICS OF A SOLUTION 10 minutes All solutions have certain characteristics in common: - it is a mixture with at least one substance dissolved in another - it is homogenous - it may be either colourless or coloured - it cannot be easily separated by simple filtration - the particles do not settle out when left to stand Students can be encouraged to think of household items that might be solutions such as cordial, vinegar and bleach. A further talking point is also to determine some household items that are liquids, but are not solutions such as milk, paint and jelly. IDENTIFY MIXTURES AS SOLUTIONS OR NOT SOLUTIONS 10 minutes Students watch 4 short videos of mixtures in a glass being stirred. After each video, the students are asked whether the mixture is a solution or not a solution. This is a further opportunity to discuss the properties of a solution before the next part of the activity introduces the concept of a solute and a solvent. LABEL THE SOLUTE AND SOLVENT OF KNOWN SOLUTIONS 10 minutes Students label the solute and solvent in four different mixtures:. Students are then introduced to the state of matter of both the solute and the solvent in common solutions: - alloy (solid/solid) - perfume (liquid/liquid) - sugar solution (solid/liquid) - carbonated water (liquid/gas) - air (gas/gas) Students then are asked to suggest another solid-liquid solution, possible examples are copper sulfate solution, salt water, instant coffee and powdered cordial in water. In each case the liquid is the solvent, and the solid is the solute. Interesting fact: Water is known as the universal solvent as more substances dissolve in it than any other solvent. This is because of the polarity of the water molecule. H2O is made up of two positive hydrogen atoms and one oxygen atom (carrying effectively two negative charges). This not only makes water a very good conductor, but also makes it able to dissociate ionic compounds (such as NaCl) with ease. Whilst water is a great solvent, it doesn't dissolve everything - students will know that you can't get a biro pen mark out of their school shirt with water - another solvent must be used. Students can hypothesise about what might be the best solvent for biro pen ink (methylated spirits). PURE SUBSTANCES AND MIXTURES © 3P Learning

16

WORKSHEET

SOLUTE + SOLVENT = SOLUTION

Question 1 Complete this sentence _____________________ + ______________________ = solution

Question 2 For each of these solutions identify the solute/s and solvent.

Question 3 Identify whether the following statements are true or false by putting a T or F next to them. (a) Solutions are homogeneous. (b) Solutes can be separated from solvents by filtration. (c) In solutions, the solvent is always water. (d) There can be more than one solute in the same solution. (e) Solutions are always colourless.

PURE SUBSTANCES AND MIXTURES © 3P Learning

17

SOLUTE + SOLVENT = SOLUTION

WORKSHEET

Question 4 Copper(II) sulfate forms a bright blue solution with water. In the beaker on the left, represent a concentrated solution of copper(II) sulfate and in the beaker on the right, represent a dilute solution of copper(II) sulfate. Label your drawings.

Question 5 Identify a: (a) liquid-liquid solution

(b) liquid-gas solution

(c) gas-gas solution

PURE SUBSTANCES AND MIXTURES © 3P Learning

18

ANSWER SHEET

SOLUTE + SOLVENT = SOLUTION

Question 1 Complete this sentence Solvent Solute _____________________ + ______________________ = solution

Question 2 For each of these solutions identify the solute/s and solvent.

Question 3 Identify whether the following statements are true or false by putting a T or F next to them. (a) Solutions are homogeneous. T (b) Solutes can be separated from solvents by filtration. F (c) In solutions, the solvent is always water. F (d) There can be more than one solute in the same solution. T (e) Solutions are always colourless. F

PURE SUBSTANCES AND MIXTURES © 3P Learning

19

SOLUTE + SOLVENT = SOLUTION

ANSWER SHEET

Question 4 Copper(II) sulfate forms a bright blue solution with water. In the beaker on the left, represent a concentrated solution of copper(II) sulfate and in the beaker on the right, represent a dilute solution of copper(II) sulfate. Label your drawings.

Question 5 Identify a (a) liquid-liquid solution Perfume (fragrant oil dissolved in alcohol) (b) liquid-gas solution Soft drink (carbon dioxide dissolved in water) (c) gas-gas solution Air (oxygen, carbon dioxide and rare gases dissolved in nitrogen)

PURE SUBSTANCES AND MIXTURES © 3P Learning

20

LESSON GUIDE

WHAT IS SUSPENSION?

This activity compares the main differences between a suspension and a solution by comparing soil and salt mixed with water. Suggested time: 15 minutes Summary of Key Learning Points Students: - identify a solution and a suspension - recognise the characteristics of a suspension IDENTIFY A SOLUTION AND A SUSPENSION 10 minutes Students watch a video demonstrating soil being mixed with water to observe the properties of a suspension. A suspension differs from a solution in that the solid, liquid or gas that is being mixed into the water does not dissolve and will eventually settle out. A good example of this is calamine lotion. There are also special types of suspensions called colloids (eg foams and gels) and emulsions (eg mayonnaise or oil and water mixed together). Two further videos are shown to demonstrate the difference between a solution (dissolved salt) and a suspension (soil and water). Students are asked to identify the suspension and write in their own words what the difference is between a solution and a suspension. (A suitable answer might be that a solution is a homogenous mixture in which soluble particles are dissolved in a liquid or gas, whereas a suspension is a heterogenous mixture in which insoluble particles are suspended in a liquid or gas.) RECOGNISE THE CHARACTERISTICS OF A SUSPENSION 5 minutes Students are introduced to the major characteristics of a suspension and are asked to match common suspensions with their type names: gas-gas (smoke in air); liquid-gas (insecticides); liquid-liquid (cordial in water); solid-gas (dust in air); solid-liquid (sand in water); solid-solid (soil).

PURE SUBSTANCES AND MIXTURES © 3P Learning

21

NOTES

PURE SUBSTANCES AND MIXTURES © 3P Learning

CHEMICAL SCIENCES [ACSSU113]

© 3P Learning

TECHNIQUES FOR SEPARATING MIXTURES

23

TOPIC SUMMARY: IntoScience topic: Techniques for separating mixtures Unmixing mixtures! Explore the many techniques used to separate mixtures.

Description: Mixtures, including solutions, contain a combination of pure substances that can be separated using a range of techniques [ACSSU113]

ACTIVITY: PHYSICAL PROPERTIES OF A SUBSTANCE It is the physical properties of a substance that allow separation techniques to work. Learn about these properties and more. Elaboration: exploring and comparing separation methods used in the home [ACSSU113-4] ACTIVITY: FILTRATION AND EVAPORATION Explore and uncover the principles behind filtration and evaporation and how they can be used, even at home. Elaboration: exploring and comparing separation methods used in the home [ACSSU113-4] ACTIVITY: DISTILLATION Learn about simple and fractional distillation as separation techniques. Elaboration: investigating and using a range of physical separation techniques such as filtration, decantation, evaporation, crystallisation, chromatography and distillation [ACSSU113-3] ACTIVITY: FILTRATION: SAVE THE FISH! Can you work out how to save the fish from their dirty tank water using a common separation technique? Elaboration: exploring and comparing separation methods used in the home [ACSSU113-4] Inquiry skills: Evaluating • Reflect on the method used to investigate a question or solve a problem, including evaluating the quality of the data collected, and identify improvements to the method [ACSIS131] • Discussing investigation methods with others to share ideas about the quality of the inquiry process [ACSIS131-1] ACTIVITY: EXPLORING MORE SEPARATION TECHNIQUES There are many interesting separation techniques which have all sorts of applications. Learn about crystallisation, sublimation, magnetic attraction, chromatography and more. Elaboration: investigating and using a range of physical separation techniques such as filtration, decantation, evaporation, crystallisation, chromatography and distillation [ACSSU113-3] ACTIVITY: THE ISLAND ACTIVITY How would you survive if you were stranded on a deserted island? Use your knowledge of evaporation to save yourself! Elaboration: investigating and using a range of physical separation techniques such as filtration, decantation, evaporation, crystallisation, chromatography and distillation [ACSSU113-3]

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LESSON GUIDE

PHYSICAL PROPERTIES OF A SUBSTANCE

Physical properties of substances are introduced, including how these properties are useful when mixtures are being separated. Suggested time: 30 minutes Summary of Key Learning Points Students: - recognise the physical properties of substances - identify equipment used for separation techniques RECOGNISE THE PHYSICAL PROPERTIES OF SUBSTANCES 15 minutes Mixtures often need to be separated so that scientists can access the pure substances from which they are made. There are many separation methods that can be used, according to the physical properties of the substances being separated. Students watch a video demonstrating magnetic separation and recall that mixtures contain substances that are not chemically combined. Question - What physical property of the paper clips makes this possible? Answer - Paper clips are magnetic, so a magnet can easily separate them from the water which is non-magnetic. The physical properties of substances are: Melting point Students can be reminded that different substances melt at different temperatures. A good example to discuss is when a magician 'bends' a spoon. The magician is actually using a special spoon made from an alloy (nickel titanium) which has a low melting point. The melting point is so low that even the heat from his hands is sufficient to melt and so 'bend' the spoon. Density Foam is less dense than water, and so floats on top of the water. Boats float because of the amount of water they displace, rather than their density being less than water. Students may observe that liquids that are not soluble and have different densities will separate out, e.g., salad dressing. Electrical conductivity Most metals are electrically conductive, but some are more conductive than others. Copper is commonly used in electrical wiring because of its electrical conductivity - however it is now very expensive! Fibre optics are commonly replacing copper wiring these days as the Internet and data transmission are becoming more common place. Heat conductivity Not all metals conduct heat in the same way and that is why some cooking pots have a copper base and an aluminium interior. The differences in heat conductivity of the metals allows for more even cooking of the food through improved convection through the food in the pot. Solubility in water Liquids that are not soluble can easily be separated using a separating funnel, and solids can be separated through evaporation. Those solids that are insoluble can be filtered. Size Solids (and gases) of different sizes are easily separated by filters or sieves. The terms 'gravel', 'sand' and 'silt' in geology all refer to the grain size of a substance rather than the chemical properties of the substance.

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PHYSICAL PROPERTIES OF A SUBSTANCE

LESSON GUIDE

Magnetic attraction Not all metals are magnetic, and some are weakly magnetic whilst others are strongly magnetic. The concept of magnetism relates to the 'domains' within the metal and the ability of the domains to maintain their alignment and hence their magnetism. If a magnet is dropped too many times it loses its magnetic properties as the domains can be bumped out of place. Boiling point Water boils at 100 degrees Celsius, but only at 1 atmospheric pressure. Water boils at a lower temperature at altitude, so it can be difficult to cook, especially cakes and foods that rely on a raising agent like yeast to make it fluffy. Extension: Students are asked which physical quality they would use to separate a bag filled with different types of sports balls. (size) Students could also be asked to discuss common household items in terms of their physical properties. For example: salt water and fresh water have different boiling points. Question: What effect does adding salt to water for cooking pasta have on the cooking time? Answer: Salt water has a higher boiling point than fresh water, so if you wait for the salted water to boil before putting in the pasta, it will cook in a shorter time as the water is hotter. IDENTIFY EQUIPMENT USED FOR SEPARATION TECHNIQUES 15 minutes Students watch a brief video demonstrating a mixture of oil and water being separated using a separating funnel. They are then asked to determine which physical property allows this method to work. (density or miscibility) You can prompt students to look up the definitions of miscible and immiscible using the Inquire menu on the top right of the screen. Students are asked to recall all the various physical properties a substance might have and apply this thinking to a situation in which they want to extract a pure substance. Sample answer: If I wanted to extract the salt from salt water, I could evaporate the water from the salt water mixture by heating it, as water's boiling point is different from salt.

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WORKSHEET

PHYSICAL PROPERTIES OF A SUBSTANCE

Question 1 (a) Describe, using examples, the difference between a physical property and a chemical property.

(b) One physical property of water is that it is transparent. Identify two other physical properties of water.

Question 2 Match the physical property to its description by drawing a line between the matching pairs.

Question 3 What differences in physical properties allows the separation of these substances? (a) Paperclips from waterPerfume (f ragrant oil dissolved in alcohol)

(b) Water from oilPer fume (fragrant oil dissolved in alcohol)

(c) Sand from siltPerf ume (fragrant oil dissolved in alcohol) TECHNIQUES FOR SEPARATING MIXTURES © 3P Learning

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PHYSICAL PROPERTIES OF A SUBSTANCE

WORKSHEET

Question 4 (Research question) Find out how the different types of scrap metal are separated and recycled. Write a paragraph to summarise what you found out.

Question 5 Describe a procedure you could use to separate a mixture of sand, salt, iron filings and water.

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ANSWER SHEET

PHYSICAL PROPERTIES OF A SUBSTANCE

Question 1 (a) Describe, using examples, the difference between a physical property and a chemical property. A physical property is a characteristic of matter that can be observed or measured without changing it, such as colour, whereas a chemical property is only observed during a chemical reaction which changes its chemical composition, such as flammability. (b) One physical property of water is that it is transparent. Identify two other physical properties of water. Two other physical properties of water are: it has relatively high melting and boiling points and it has a density of 1g/cm3. Question 2 Match the physical property to its description by drawing a line between the matching pairs.

Question 3 What differences in physical properties allows the separation of these substances? (a) Paperclips from water Magnetism (b) Water from oil Solubility (c) Sand from silt Size

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PHYSICAL PROPERTIES OF A SUBSTANCE

ANSWER SHEET

Question 4 (Research question) Find out how the different types of scrap metal are separated and recycled. Write a paragraph to summarise what you found out. Suggested answer: Different types of scrap metal can be separated by sorting techniques. Examples are using magnets to separate ferrous from non-ferrous materials. An eddy current separator uses a powerful magnetic field to sort all of the non-ferrous materials which are metallic from waste, non-useful materials. Other scrap metal separation techniques include flotation (gravitational separation), optical separation and manual separation. Question 5 Describe a procedure you could use to separate a mixture of sand, salt, iron filings and water. Remove the iron filings using a magnet. Filter the sand, salt and water through filter paper, separating the sand. Boil the salt and water until all of the water evaporates, leaving the salt remaining.

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LESSON GUIDE

FILTRATION AND EVAPORATION

This activity explores the use of filtration and evaporation as separating techniques for soluble and insoluble mixtures. Suggested time: 15 minutes Summary of Key Learning Points Students: - compare filtration and evaporation as methods of separation COMPARE FILTRATION AND EVAPORATION AS METHODS OF SEPARATION 15 minutes Students are asked to consider which technique is best used to separate a solid dissolved in a liquid (evaporation) and a solid that does not dissolve in a liquid (filtration). Filtration is first explored as students observe how filter paper and a funnel can be used to separate a solid from a liquid. In the home this can be seen through a coffee filter or on a coarser level, a tea bag. Evaporation on the other hand is used when you don't need to keep the liquid (as it escapes during the evaporation process) but do want to keep the solute (solid). Seawater is provided as a good example of a solution from which the salt could be extracted by evaporation. They are asked to nominate another solution. Cordial or sugar and water solutions are possible answers. Science extra: A good example of evaporation is a salt pan in which salt is extracted from salt water. Students can do this at home with either a salt or sugar solution left to stand for a length of time until the solvent evaporates. Talking point: Ask students to consider what they might be able to do if they wanted to keep the fresh water that is evaporated off a salt pan (distillation will be covered in this unit of work also). Question: You have made a salad dressing which contains salt, pepper, oil, balsamic vinegar and dissolved sugar. How can these be separated? Sample answer: The pepper can be filtered out using filter paper and a funnel. The oil can then be separated from the vinegar, sugar and salt using a separating funnel. The vinegar can be evaporated off and the salt and sugar will remain. Talking point: The above method will still leave the salt and the sugar mixed together. What possible methods might be used to separate the two? They are both soluble in water, but they must have other physical properties that are different in order to be separated. The answer does lie in the solubility of the two substances: salt is not soluble in alcohol. So if the remaining salt and sugar are then mixed with alcohol, the salt can be filtered from the sugar/alcohol solution by using filter paper and a funnel. Try this in the lab!

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DISTILLATION

LESSON GUIDE

Students watch videos demonstrating simple distillation and fractional distillation techniques and recognise the lab equipment used. Suggested time: 45 minutes Summary of Key Learning Points Students: - observe the process of simple distillation - recognise the lab equipment used in simple distillation - observe the process of fractional distillation - explore the fractionating column OBSERVE THE PROCESS OF SIMPLE DISTILLATION 10 minutes Students watch a video in which the laboratory equipment for distilling copper sulfate solution is used. Students observe that the liquid extracted in the condenser is called the distillate. Ask the class what other common mixtures may be able to be separated using this method - red wine, vinegar, eucalyptus oil, lavender oil and many other household products can be separated using simple distillation. RECOGNISE THE LAB EQUIPMENT USED IN SIMPLE DISTILLATION 10 minutes Students can watch the video again and determine which pieces of equipment match those in the diagram presented. Students can discuss what each part of the equipment is used for, in particular noting the condenser as the main distinguisher between evaporation and distillation. OBSERVE THE PROCESS OF FRACTIONAL DISTILLATION 15 minutes Students watch a video demonstrating fractional distillation in the lab. This is a good opportunity for a class discussion on the similarities and differences between simple and fractional distillation. Science extra: Fractional distillation in an oil refinery The extraction of tar, diesel, petroleum and high-octane fuel for aeroplanes is a critical part of modern day life. This section may be of particular interest, as students explore what crude oil is able to be separated into and the reasons why crude oil is so valuable in our society. EXPLORE THE FRACTIONATING COLUMN 10 minutes In the previous part of the activity, students gain an understanding of why we use fractional distillation as a method of extraction, but without the detail on the fractionating column itself. The diagram and text explain that fractional distillation is effective because of the varying boiling points of the constituents of a mixture. For example, tar has a low boiling point, and so condenses out first in the fractionating column, whereas jet fuel has a much higher boiling point and so condenses out higher up the column. Students are asked to explain two statements: 1. The closer the boiling points of the liquids, the longer the fractionating column. 2. The longer the fractionating column, the longer the time taken for distillation to take place. Extension activity: Research the different boiling points of common refrigerant gases (and those used in freezers) and how fractional distillation can be used to recycle these gases to 're-gas' a fridge or a freezer.

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LESSON GUIDE

FILTRATION: SAVE THE FISH!

Students use their problem solving skills and knowledge of separation methods to save the fish from the polluted water. Suggested time: 30 minutes Summary of Key Learning Points Students: - use knowledge and problem solving skills to clarify water. USE KNOWLEDGE AND PROBLEM SOLVING SKILLS TO CLARIFY WATER 30 minutes Students are introduced to a dilemma. The water in the fish tank is too dirty. If you can't filter the water, the fish will surely die! They are presented with two tanks and various filtration equipment in order to solve the problem. Students must first work out which apparatus may be the best to use (in this case, the towel) and then carry out the filtration. Finally they must move the fish into the new tank to find out if their filtration method was successful in saving the fish. This exercise involves some trial and error, but also requires knowledge and problem solving skills. It is a good opportunity to remind students that not only specific scientific equipment can be used to filter water. In fact, often we must make use of everyday objects and equipment. Extension: Students may research methods of filtering and cleaning water to make it potable. There are many methods of doing this, but those that are solar powered will be most favourable in areas where there is no power grid. (additional 30 minutes)

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EXPLORING MORE SEPARATION TECHNIQUES

LESSON GUIDE

Students explore further techniques for extracting different substances from mixtures. Suggested time: 45 minutes Summary of Key Learning Points Students: - identify the process of sublimation and distinguish between melting and sublimation - identify the process of crystallisation - identify the process of magnetic attraction - identify the process of chromatography - research further separation techniques IDENTIFY THE PROCESS OF SUBLIMATION AND DISTINGUISH BETWEEN MELTING AND SUBLIMATION 10 minutes Students watch a video demonstrating the sublimation of solid iodine. WARNING - If this experiment is done in class, it needs to be done by the teacher in a fume cupboard as iodine gas is poisonous! The important thing for students to observe is that the solid goes directly to gas, and at no stage becomes a liquid. Contrast this with heating solid copper sulfate, which will melt into liquid form when heated. In terms of a separation method, substances that sublimate, such as iodine, can be separated from (for example) a salt solution by heating. Students distinguish between melting and sublimation. If a substance changes from solid to gas via the liquid state, then it is melting rather than subliming. Examples of other substances that sublime are solid carbon dioxide (dry ice) and naphthalene (moth balls). Talking point: liquid iodine is often used for medical and health purposes. If iodine is solid at room temperature, and then sublimes to a gas - how is liquid iodine made and stored at room temperature? Answer: liquid iodine can be made from solid iodine by heating it to just above its melting point (113.7ºC) and then cooling it slowly so it remains liquid at room temperature. IDENTIFY THE PROCESS OF CRYSTALLISATION 5 minutes Students watch a video that shows the formation of copper sulfate crystals and understand that crystallisation is the process by which a solute separates from a solution in the form of crystals. IDENTIFY THE PROCESS OF MAGNETIC ATTRACTION 5 minutes Students watch a video in which paper clips are separated from a beaker of water using magnetic attraction. The use of magnetic attraction to recover iron and steel from scrap metal is introduced and students are asked why iron and steel are recovered. These materials can be melted and re-used, helping to make their manufacture more economically viable, reduce environmental impacts and conserve the Earth's natural mineral resources. Students might be interested to learn that around 1/3 of the world's total steel production is sourced from recycled scrap metal.

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LESSON GUIDE

EXPLORING MORE SEPARATION TECHNIQUES

IDENTIFY THE PROCESS OF CHROMATOGRAPHY 5 minutes Students learn that there are a number of different types of chromatography (paper, liquid, gas and thin-layer chromatography). They watch a video in which paper chromatography is used to separate small amounts of coloured substances, and they understand that solubility is the key factor in this separation technique. Students learn some key applications of chromatography to: identify dyes used in foods, identify banned drugs in athletes and to identify the dyes used in inks. Students are asked why detectives might use ink chromatography. Answer: to identify the ink used in ransom notes or counterfeiting, to analyse the dye composition of fibres found at crime scenes and in similar aspects of detective investigation. RESEARCH FURTHER SEPARATION TECHNIQUES 20 minutes Students are asked to research one other separation technique and write 100 words about it. They may choose from: centrifugation, decantation and absorption. Centrifugation is separation by spinning. Heavier substances are forced to the bottom and lighter substances rise to the top. At a blood bank, red and white blood cells are separated from platelets and plasma in a centrifuge. The same principle is used in the spin cycle of a washing machine. In decantation, a mixture is poured into a container and given time for the sediment to settle to the bottom. Then the liquid is carefully poured off the top. People decant wine to remove sediment and use a similar technique when pouring the liquid from a pot of cooked vegetables, pasta or rice. Physical and chemical absorption techniques are commonly used to separate gases. In absorption, substances present in gas are absorbed into liquid. Absorption is used in chemical production and in the petroleum industry.

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THE ISLAND ACTIVITY

LESSON GUIDE

Students are presented with a desert island scenario in which they must make drinking water from seawater, using only what is available on the island. Suggested time: 30 minutes Summary of Key Learning Points Students: - identifying potential uses of natural and man-made objects - problem solving to create drinking water from seawater IDENTIFYING POTENTIAL USES OF NATURAL AND MAN-MADE OBJECTS 5 minutes Students are presented with a number of natural and man-made items with which to create drinking water from seawater. Each item has its own properties which can be applied to the scenario. Each object provides a good opportunity to discuss its potential use in the situation presented and other potential uses it might have, e.g. shelter, hunting. In this particular situation, each object has only one use for the purposes of solving the problem presented. The physical properties of the man-made items available on the island are also important, e.g. plastic vs metal bucket. A plastic bucket would melt when heated, so an alternative to a plastic bucket must be used. PROBLEM SOLVING TO CREATE DRINKING WATER FROM SEAWATER 25 minutes This activity could be run in class by a few alternative methods: - allow students to work on their own through trial and error to solve the problem, then encourage a selection of students to present their solution and thinking to the class. - work together as a class or in small groups to think through the problem and solution first, without doing it. Present the different strategies to the class, then students choose which strategy they are going to try. Students then carry out the strategy and observe whether it is successful or not. The result of each strategy can then be discussed by the class. Talking point: If the situation were different, i.e. no metal bucket and no flint - what other strategies might be possible to make drinking water from seawater? An interesting scenario to present is being stranded at sea. "If you were drifting in a lifeboat for days, surrounded by seawater, but desperately thirsty, what could you do?" The parameters: - seawater makes you very ill if you drink it - so that is not advisable! - you can't make a fire because you don't have matches or fuel. - you do have a piece of plastic or a plastic bag. - you do have a lot of time! A possible solution is to use the plastic bag to cover over some of the seawater in the bottom of the boat. Hopefully the temperature is warm enough to cause it to evaporate, and then you could drink the water that runs off the plastic bag. This would be a very slow process, and you would only get a few drops, but it might be enough to keep you alive.

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CHEMICAL SCIENCES [ACSSU152]

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TOPIC SUMMARY: IntoScience topic: Elements, compounds and mixtures Understand elements, compounds and mixtures while getting to know the periodic table.

Description: Differences between elements, compounds and mixtures can be described at a particle level [ACSSU152]

ACTIVITY: CLASSIFICATION OF MATTER What exactly is an element, a compound or a mixture? Is a metal a pure substance? Analyse real-world samples to understand how matter is classified. Elaboration: modelling the arrangement of particles in elements and compounds [ACSSU152-1] Inquiry skills: Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • Constructing tables, graphs, keys and models to represent relationships and trends in collected data [ACSSU145-1] General capabilities: Critical and Creative Thinking ACTIVITY: CHANGING MODELS OF THE ATOM From ancient times to today, our understanding of the basic unit of matter, the atom, has changed dramatically. Take a journey through time to see how the atomic model has transformed. Elaboration: modelling the arrangement of particles in elements and compounds [ACSSU152-1] Inquiry skills: Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • Constructing tables, graphs, keys and models to represent relationships and trends in collected data [ACSSU145-1] ACTIVITY: STRUCTURE OF THE ATOM Discover what atoms are made up of and how to represent them correctly. Challenge yourself to write the electron configurations of the first 18 elements. Elaboration: recognising that elements and simple compounds can be represented by symbols and formulas [ACSSU152-2] ACTIVITY: INTRODUCTION TO THE PERIODIC TABLE Welcome to the periodic table! This important reference contains the ingredients to all matter in the universe. Get to know the groups, periods and special names given to certain elements. Elaboration: locating elements on the periodic table [ACSSU152-3] Inquiry skills: Processing and Analysing Data and Information • Construct and use a range of representations, including graphs, keys and models to represent and analyse patterns or relationships, including using digital technologies as appropriate [ACSIS144] • Describing measures of central tendency and identifying outliers for quantitative data [ACSSU144-1] General capabilities: Critical and Creative Thinking © 3P Learning

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TOPIC SUMMARY:

ELEMENTS, COMPOUNDS AND MIXTURES

ACTIVITY: PROPERTIES AND USES OF ELEMENTS A meteorite has caused problems, but can it also be a solution? Experiment with the elements to uncover properties of metals and non-metals and find out if the meteorite might be useful. Elaboration: locating elements on the periodic table [ACSSU152-3] Inquiry skills: Processing and Analysing Data and Information • Construct and use a range of representations, including graphs, keys and models to represent and analyse patterns or relationships, including using digital technologies as appropriate [ACSIS144] • Describing measures of central tendency and identifying outliers for quantitative data [ACSSU144-1] General capabilities: Critical and Creative Thinking ACTIVITY: COMPARING COMPOUNDS Investigate how and why atoms bond together to form compounds. The two classes of compounds, ionic and covalent, have quite different properties. Can you tell which is which? Elaboration: recognising that elements and simple compounds can be represented by symbols and formulas [ACSSU152-2] Inquiry skills: Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • Constructing tables, graphs, keys and models to represent relationships and trends in collected data [ACSSU145-1] General capabilities: Critical and Creative Thinking ACTIVITY: NAMING COMPOUNDS Decipher what seems like a whole new language by learning how to name compounds made of only two elements. Master the name game and prove your chemical talent! Elaboration: recognising that elements and simple compounds can be represented by symbols and formulas [ACSSU152-2] Inquiry skills: Evaluating • Use scientific knowledge and findings from investigations to evaluate claims [ACSIS234] • Identifying the scientific evidence available to evaluate claims [ACSIS234-1] deciding whether or not to accept claims based on scientific evidence [ACSIS234-2] General capabilities: Critical and Creative Thinking

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CLASSIFICATION OF MATTER

LESSON GUIDE

Students discover the different types of matter in the world around them by examining five different samples from the biodome. Suggested time: 45 minutes Summary of Key Learning Points Students: - identify that all matter can be divided into two categories: pure substances and mixtures - understand that the two types of pure substances are elements and compounds - learn that compounds can be either ionic or covalent - realise that there are two types of mixtures: homogeneous and heterogeneous - find out that there are many examples of each type of matter in the world around us CLASSIFICATION OF MATTER - ANALYSIS 10 minutes Five samples have been taken from the biodome. Students run them through the analyser to find their major components. Discuss the different models with students, noting how the ionic lattices differ from the molecular substances. For river water, explain that sodium chloride and sodium hydrogencarbonate do not exist as solids in the water; the ions would be moving freely through the solution. The metal must be a type of steel since its principal components are iron and carbon. Note that the crystal structures are simplified representations. Talking points: How do molecules differ from lattice structures? (Answer = they exist as discrete units rather than any number of atoms/ions joined in a 3D network) How are ionic lattices similar to, and different from, covalent network structures? (Answer = both are made of different elements but ionic lattices are made of alternating positive and negative ions while the covalent networks are made of atoms with outer shells overlapped to allow electron sharing) Why were no lattice structures found in air? (Answer = their melting and boiling points are far too high for them to be gaseous at normal temperatures) MIX AND MATCH 15 minutes On this page students match definitions and terms. For extra practice, they could draw up a table of the terms and definitions and fill it in as they go. Answers: (Inquiry point 1) Compound: Pure substance made of two or more different elements chemically combined in a fixed ratio by mass. They are formed when elements react and can be broken down into their elements by chemical methods, but not by physical methods. Element: Pure substance composed of atoms that all have the same atomic number (same number of protons in the nucleus). They cannot be broken down into simpler substances by either chemical or physical means. Homogeneous mixture: Mixture that has evenly distributed components and the different parts of the mixture are not visible. Heterogeneous mixture: These mixtures contain components that are not evenly distributed; the different components are clearly visible. Atom: Building blocks of all matter. They are composed of a central positively-charged nucleus surrounded by an electron cloud.

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LESSON GUIDE

CLASSIFICATION OF MATTER

Pure substance: A substance with constant composition that can be represented by a chemical formula. It has distinct physical and chemical properties. Mixture: Composed of two or more different substances physically combined. They do not have constant properties and cannot be represented by a single chemical formula. Components can be separated by physical methods such as evaporation or filtration. Ionic compound: Formed when metals bond to non-metals in a fixed ratio by mass. Covalent compound: Formed from two or more different non-metals combined in a fixed ratio by mass. Matter: Anything that has mass and takes up space. Made of atoms. PUTTING IT ALL TOGETHER 10 minutes This page has a partially-completed flow diagram to show the different levels of organisation in the classification of matter. There is more than one answer possible for the examples that can be used. Those listed below are suggestions only. Answers: (Inquiry point 2) Elements, example: carbon Metals, example: iron Non-metals, example: argon Compounds, example: calcium carbonate Covalent compounds, example: water Ionic compounds, example: sodium chloride Heterogeneous mixtures, example: soil Homogeneous mixtures, example: air Talking point: What other categories could be used to classify matter? WHAT AM I? 10 minutes Four more samples have been taken from the biodome and students must examine them to work out which category of matter they fall into. Answers: Sample 1: Pure substance/compound (Inquiry point 3) Sample 2: Mixture/elements (Inquiry point 4) Sample 3: Pure substance/element (Inquiry point 5) Sample 4: Mixture/compounds & elements (Inquiry point 6) Extra activity: Get students to list ten things in the room around them and write down which category or categories of matter the listed items would fall into.

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CLASSIFICATION OF MATTER

LESSON GUIDE

Suggested completion levels Basic - Inquiry point goal = 2 Students at this level will: identify that all matter is either a pure substance or a mixture; list at least three different types of matter; define the terms 'atom', 'element' and 'compound'. Core - Inquiry point goal = 4 Students at this level will: be able to draw a simple flow chart to classify matter; give simple definitions of all the terms in the flow chart; identify an example of each type of matter. Advanced - Inquiry point goal = 6 Students at this level will: draw a detailed flow chart to classify matter and suggest further levels of classification; describe each term in the flow chart with examples; write the chemical formulas of the examples given in the 'pure substances' categories.

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WORKSHEET

CLASSIFICATION OF MATTER

Question 1 These terms and definitions are jumbled up. Draw a line to correctly match each of these terms to its definition.

Question 2 Identify an example of: (a) an element Perfume (fragrant oil dissolved in alcohol)

(b) a homogeneous mixture Perfume (fragrant oil dissolved in alcohol)

(c) a covalent compound Perfume (fragrant oil dissolved in alcohol)

(d) an ionic compound Perfume (fragrant oil dissolved in alcohol)

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CLASSIFICATION OF MATTER

WORKSHEET

Question 3 These three boxes contain different gases. Choose one of the labels (i)-(v) for each of the boxes (a)-(c). Write the correct label underneath each box. (i) a pure element (ii) a mixture of elements (iii) a pure compound (iv) a mixture of compounds (v) a mixture of elements and compounds

Question 4 In the boxes below, draw the substance indicated.

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WORKSHEET

CLASSIFICATION OF MATTER

Question 5 Using all the terms from Question 1, draw a flow chart to show how matter is categorised. The flow chart has been started for you.

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CLASSIFICATION OF MATTER

ANSWER SHEET

Question 1 These terms and definitions are jumbled up. Draw a line to correctly match each of these terms to its definition.

Question 2 Identify an example of: (a) an element Carbon (fragrant oil dissolved in alcohol) (b) a homogeneous mixture AirPerfume (fragrant oil dissolved in alcohol) (c) a covalent compound WaterPerfume (fragrant oil dissolved in alcohol) (d) an ionic compound Salt (NaCl)Perfume (fragrant oil dissolved in alcohol)

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ANSWER SHEET

CLASSIFICATION OF MATTER

Question 3 These three boxes contain different gases. Choose one of the labels (i)-(v) for each of the boxes (a)-(c). Write the correct label underneath each box. (i) a pure element (ii) a mixture of elements (iii) a pure compound (iv) a mixture of compounds (v) a mixture of elements and compounds

Question 4 In the boxes below, draw the substance indicated.

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CLASSIFICATION OF MATTER

ANSWER SHEET

Question 5 Using all the terms from Question 1, draw a flow chart to show how matter is categorised. The flow chart has been started for you.

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LESSON GUIDE

CHANGING MODELS OF THE ATOM

Students are taken on a journey showing how ideas of the atom have changed over a period of more than two thousand years. Suggested time: 20 minutes Summary of Key Learning Points Students: - think about what matter is made of - understand that early ideas are based on visual references as no technology existed back then to look at matter more closely - discover changes made to the atomic model over time - relate changes to the atomic model to new evidence coming to light thanks to improved technology WHAT DID WE USED TO THINK? 5 minutes Students can chop the wood by selecting it. Selecting the pieces allows them to chop it up even more. This relates to the first question on the page. Discuss with students the idea that for thousands of years, all people knew about matter was what they could see with their naked eye. The Greek philosophers' ideas on what made up matter were not based on scientific evidence. Lacking the technology we have today, ideas were difficult to prove or disprove. The questions on this page were the same questions the Greek philosophers were asking back in 300-400 BCE. Try to get students to look at the questions from their point of view. Suggested answers: (Inquiry point 1) Smaller than can be seen with the naked eye! No! But a couple of thousand years ago there was a school of thought that said 'yes' to that question. OPPOSING VIEWS 5 minutes Emphasise to students that Democritus (460-370BCE) preceded Aristotle (384-322BCE). Class activity: Have a debate, with half the class researching and then arguing for Aristotle's point of view, while the rest of the class researches and then argues for Democritus's point of view. ATOMS 5 minutes Students select the atoms to see how they were viewed in ancient times. Answer: Matter is made of atoms Atoms cannot be divided further (Inquiry point 2) Although atoms are made of sub-atomic particles, we still don't say they can be 'divided' as the atom is the base unit of matter. The second question asks students to put themselves in Democritus's place in thinking about air. Suggested answer: Light and moving (Inquiry point 3)

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ATOMIC STRUCTURE 5 minutes This page allows students to use the slider to move forward and back in time to see how the atomic model has changed. They might notice the dates show a giant gap in time between the Greek philosophers and Dalton. This is because not much happened in terms of changing ideas of the atom in that time. That gap also contains large periods of superstition where new ideas could have left you open to accusations of witchcraft! Suggested completion levels Basic - Inquiry point goal = 2 Students at this level will: identify that ideas about the atom have changed over time. Core - Inquiry point goal = 3 Students at this level will: understand that the atomic model has been modified over time as new evidence has come to light; identify at least two different models of the atom. Advanced - Inquiry point goal = 3 Students at this level will: explain how the atomic model has changed over time, identifying the major models along the way and the person who proposed each one; understand that changes to the model occurred as improved technology allowed evidence to come to light that contradicted the previous model.

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WORKSHEET

CHANGING MODELS OF THE ATOM

Over the past two and a half thousand years, our view of the atom has changed dramatically. Complete the questions below, and along the way you will be experiencing the major stepping stones to our current atomic model. Democritus (born 460BCE) Evidence available: only what could be seen with the naked eye. Here are a few of Democritus's beliefs: (i) Everything is made of atoms (ii) Atoms have different sizes (iii) Atoms have different shapes and textures (iv) Atoms can bond together because they have hooks or other linking structures on their surfaces (v) Different tastes occur due to different atom properties, for example if something is bitter it is because its atoms are sharp and jagged Question 1 Which of these do we still believe in today? Perfume (fragrant oil dissolved in alcohol)

Question 2 What evidence could Democritus have had for his beliefs?

John Dalton (1803) New evidence available: 36 elements were known; Law of Conservation of Mass; reacting ratios of elements in compounds; rough relative atomic weights for certain elements Dalton believed: (i) All matter is made of atoms (ii) Atoms are solid, indestructible spheres (iii) Atoms cannot be broken down further (iv) Different elements have different types of atoms (v) All atoms of the same element have the same mass and same properties (vi) Compounds are formed from two or more different elements combining in simple, whole number ratios (vii) Atoms cannot be made and they can't be destroyed (viii) In a chemical reaction, atoms are re-arranged

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Question 3 Which of these do we still believe today? Perfume (fragrant oil dissolved in alcohol)

Question 4 Dalton erroneously thought the formula of water was OH and the formula of ammonia was NH. What are the correct formulas of these compounds? Perfume (fragrant oil dissolved in alcohol)

J. J. Thomson (1904) New evidence available: 84 elements known; increased understanding about radiation Thomson's experiment: Thomson studied cathode ray tubes, which were tubes containing a near vacuum. He ran high voltages across the tube and found that 'rays' were emitted from the cathode. The fact that the particles in the rays were bent towards the positive plate showed him they were negatively charged. He called them 'corpuscles' (later, electrons) and concluded they were part of all matter.

Question 5 Describe Thomson's atomic model. Perfume (fragrant oil dissolved in alcohol)

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CHANGING MODELS OF THE ATOM

Ernest Rutherford (1911) New evidence available: the existence of electrons; greater understanding about the nature of alpha and beta radiation Rutherford's experiment: firing positively charged alpha particles (helium nuclei) at a very thin sheet of gold adhered to glass. This was surrounded by a circular, zinc sulfide coated screen that flashed when hit by an alpha particle. This showed that most past through, but some are deflected and a few bounced back. At the time he said this was as surprising as shooting a cannonball at a piece of tissue paper and having it bounce back at you. This contradicted Thomson's model because positive charges should have been able to move straight through his atom.

Question 6 Describe Rutherford's atomic model and explain how his experiment led to this model.

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Niels Bohr (1922) New evidence available: 86 elements known; existence of electrons and nucleus; further data from radiation experiments; spectra studies; concept of atomic number Bohr's experiment: Bohr studied the emission spectra of hydrogen and found that the lines always appeared in the same places. From this he concluded that electrons move in energy levels called shells. Matter can absorb or emit energy only by electrons moving between shells and the shells are always the same size for any particular atom.

Question 7 How was Bohr's atomic model different from Rutherford's atomic model?

James Chadwick (1932) New evidence available: 88 elements known, first particle accelerators had been built Chadwick's experiment: Chadwick repeated other people's experiments firing alpha particles at beryllium. He had created a new device for measuring radiation specifically to search for the neutral particle he believed must exist, since atomic mass measurements were always higher than the atomic number. Sure enough, he found it and called it the 'neutron'. He calculated its mass to be 0.1% higher than a proton. Question 8 How did Chadwick's model of the atom differ from Bohr's?

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WORKSHEET

CHANGING MODELS OF THE ATOM

Wave-mechanical atom (current model) New evidence available: 114 elements known; vast amounts of information supplied from particle accelerator experiments. This model is based on quantum mechanics and is far too complicated to try to explain simply. Suffice to say that it is a mathematically-described model that has been frequently modified to incorporate new discoveries.

Question 9 Do you think this model will ever change again? Explain your answer.

Question 10 On the timeline, sketch each of the major atomic models in the appropriate place.

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Over the past two and a half thousand years, our view of the atom has changed dramatically. Complete the questions below, and along the way you will be experiencing the major stepping stones to our current atomic model. Democritus (born 460BCE) Evidence available: only what could be seen with the naked eye. Here are a few of Democritus’s beliefs: (i) Everything is made of atoms (ii) Atoms have different sizes (iii) Atoms have different shapes and textures (iv) Atoms can bond together because they have hooks or other linking structures on their surfaces (v) Different tastes occur due to different atom properties, for example if something is bitter it is because its atoms are sharp and jagged Question 1 Which of these do we still believe in today? (i), (ii)Perfume (fragrant oil dissolved in alcohol) Question 2 What evidence could Democritus have had for his beliefs? His evidence was only what he could observe with his senses. The rest was a result of his imagination. For example, he observed that some things tasted bitter and unpleasant. He imagined this was because the atoms making up the substances were jagged, as though they were cutting into his tongue. John Dalton (1803) New evidence available: 36 elements were known; Law of Conservation of Mass; reacting ratios of elements in compounds; rough relative atomic weights for certain elements Dalton believed: (i) All matter is made of atoms (ii) Atoms are solid, indestructible spheres (iii) Atoms cannot be broken down further (iv) Different elements have different types of atoms (v) All atoms of the same element have the same mass and same properties (vi) Compounds are formed from two or more different elements combining in simple, whole number ratios (vii) Atoms cannot be made and they can’t be destroyed (viii) In a chemical reaction, atoms are re-arranged

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CHANGING MODELS OF THE ATOM

Question 3 Which of these do we still believe today? (i), (iii), (iv), (vi), (vii), (viii)Perfume (fragrant oil dissolved in alcohol) Question 4 Dalton erroneously thought the formula of water was OH and the formula of ammonia was NH. What are the correct formulas of these compounds? H2O, NH3

J. J. Thomson (1904) New evidence available: 84 elements known; increased understanding about radiation Thomson’s experiment: Thomson studied cathode ray tubes, which were tubes containing a near vacuum. He ran high voltages across the tube and found that ‘rays’ were emitted from the cathode. The fact that the particles in the rays were bent towards the positive plate showed him they were negatively charged. He called them ‘corpuscles’ (later, electrons) and concluded they were part of all matter.

Question 5 Describe Thomson’s atomic model.Perfume (fragrant oil dissolved in alcoho It was a diffuse, positively charged sphere with negative particles embedded in it.

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CHANGING MODELS OF THE ATOM

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Ernest Rutherford (1911) New evidence available: the existence of electrons; greater understanding about the nature of alpha and beta radiation Rutherford’s experiment: firing positively charged alpha particles (helium nuclei) at a very thin sheet of gold adhered to glass. This was surrounded by a circular, zinc sulfide coated screen that flashed when hit by an alpha particle. This showed that most past through, but some are deflected and a few bounced back. At the time he said this was as surprising as shooting a cannonball at a piece of tissue paper and having it bounce back at you. This contradicted Thomson’s model because positive charges should have been able to move straight through his atom.

Question 6 Describe Rutherford’s atomic model and explain how his experiment led to this model. It had a small, positively charged nucleus with tiny, negatively-charged particles moving around it. This model was the only way to explain why most alpha particles passed through the gold foil and just a few were deflected.

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ANSWER SHEET

CHANGING MODELS OF THE ATOM

Niels Bohr (1922) New evidence available: 86 elements known; existence of electrons and nucleus; further data from radiation experiments; spectra studies; concept of atomic number Bohr’s experiment: Bohr studied the emission spectra of hydrogen and found that the lines always appeared in the same places. From this he concluded that electrons move in energy levels called shells. Matter can absorb or emit energy only by electrons moving between shells and the shells are always the same size for any particular atom.

Question 7 How was Bohr’s atomic model different from Rutherford’s atomic model?I In Bohr’s model, the electrons travel in different energy levels called shells. In Rutherford’s model, the electrons were not arranged in shells.

James Chadwick (1932) New evidence available: 88 elements known, first particle accelerators had been built Chadwick’s experiment: Chadwick repeated other people’s experiments firing alpha particles at beryllium. He had created a new device for measuring radiation specifically to search for the neutral particle he believed must exist, since atomic mass measurements were always higher than the atomic number. Sure enough, he found it and called it the ‘neutron’. He calculated its mass to be 0.1% higher than a proton. Question 8 How did Chadwick’s model of the atom differ from Bohr’s? Chadwick’s model included neutrons in the nucleus, unlike Bohr’s model.

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Wave-mechanical atom (current model) New evidence available: 114 elements known; vast amounts of information supplied from particle accelerator experiments. This model is based on quantum mechanics and is far too complicated to try to explain simply. Suffice to say that it is a mathematically-described model that has been frequently modified to incorporate new discoveries.

Question 9 Do you think this model will ever change again? Explain your answer. It is being modified fairly frequently, although some believe that high energy physicists have pretty much found out all there is to know about the atom. We’ll see what the future holds.

Question 10 On the timeline, sketch each of the major atomic models in the appropriate place.

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LESSON GUIDE

STRUCTURE OF THE ATOM

Students discover the major sub-atomic particles and learn about the electron configurations of the first 20 elements. Suggested time: 35 minutes Summary of Key Learning Points Students: - discover the three main sub-atomic particles and their characteristics - find out how to represent particular atoms using nuclide symbol notation - understand how many electrons can fit in the first few electron shells - observe the electron configurations of the first 20 elements - write the electron configurations for the first 18 elements STRUCTURE OF THE ATOM 5 minutes The first page features a neon-20 atom. The nucleus is a 3D object that can be 'grabbed' and rotated. Have students start by counting the number of protons (red) and the number of neutrons (blue). They can then confirm their count using the 'explore' buttons. The main properties of each sub-atomic particle are given. Emphasise that the electrons are much smaller than the protons and neutrons. HOW TO REPRESENT ATOMS 5 minutes This page shows how to represent atoms using nuclide symbol notation. It should also be emphasised that the number of electrons will only equal the number of protons in a neutral atom. Ions will obviously have unequal numbers of protons and electrons. Class activity: Have students work out how many protons, neutrons and electrons each of neon's isotopes has. Also have them write the nuclide symbols for carbon's isotopes, carbon-12, carbon-13 and carbon-14. CHALLENGE 10 minutes Students look at several nuclide symbols and write the appropriate numbers in the data card. Answers: Calcium-40: mass number = 40; atomic number = 20; number of protons = 20; number of neutrons = 20; number of electrons = 20 (Inquiry point 1) Carbon-14: mass number = 14; atomic number = 6; number of protons = 6; number of neutrons = 8; number of electrons = 6 (Inquiry point 2) Nitrogen-14: mass number = 14; atomic number = 7; number of protons = 7; number of neutrons = 7; number of electrons = 7 (Inquiry point 3) Krypton-85: mass number = 85; atomic number = 36; number of protons = 36; number of neutrons = 49; number of electrons = 36 (Inquiry point 4) Potassium-39: mass number = 39; atomic number = 19; number of protons = 19; number of neutrons = 20; number of electrons = 19 (Inquiry point 5) ADDING ELECTRONS 5 minutes Students use the slider to view the first 20 elements with their election configurations. Tell them that the maximum number of electrons in any shell = 2 x (shell number)2. This means that the third shell fits 18 electrons, but it is stable with 8. Due to sub-shell filling order, two electrons go into the 4s shell before the 3d orbitals fill. This is why the electron configuration of potassium is 2, 8, 8, 1 not 2, 8, 9, and calcium's is 2, 8, 8, 2 not 2, 8, 10. ELEMENTS, COMPOUNDS AND MIXTURES © 3P Learning

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5. ELECTRON CONFIGURATIONS 10 minutes By selecting each element in turn, students can write the electron configuration of the first 18 elements. Answers: Hydrogen = 1 Helium = 2 Lithium = 2, 1 Beryllium = 2, 2 Boron = 2, 3 Carbon = 2, 4 Nitrogen = 2, 5 Oxygen = 2, 6 Fluorine = 2, 7 Neon = 2, 8 Sodium = 2, 8, 1 Magnesium = 2, 8, 2 Aluminium = 2, 8, 3 Silicon = 2, 8, 4 Phosphorus = 2, 8, 5 Sulfur = 2, 8, 6 Chlorine = 2, 8, 7 Argon = 2, 8, 8 (Inquiry point 6) Suggested completion levels Basic - Inquiry point goal = 2 Students at this level will: identify the three main sub-atomic particles; recognise what the numbers in a nuclide symbol mean; write the electron configurations for the first 10 elements. Core - Inquiry point goal = 4 Students at this level will: describe the three main sub-atomic particles and their characteristics; understand nuclide symbols; write nuclide symbols for given isotopes; write the electron configurations of the first 18 elements. Advanced - Inquiry point goal = 6 Students at this level will: describe the three main sub-atomic particles and their characteristics; understand nuclide symbols; write nuclide symbols for given isotopes; write the electron configurations of the first 20 elements; explain the unexpected electron configurations for potassium and calcium.

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STRUCTURE OF THE ATOM

Question 1 Draw a sodium atom with 11 protons, 12 neutrons and 11 electrons. Include a key with your answer.

Question 2 Complete the spaces in these paragraphs using these words. Each word is used once.

mass; 11; protons; small; nucleus; element; electrons; sodium; grape; neutrons

The atom I have just drawn is the element ___________________ (Na). Its position on the periodic table is eleventh, and it has the atomic number __________________. Each ___________________ on the periodic table has a different atomic number. This number represents the number of _____________________ an atom of a particular element contains in its nucleus. In a neutral (uncharged) atom, the number of protons = the number of ____________________ .

Each atom also has a _________________ number. The mass number represents the number of particles in the ________________. The mass number represents the number of protons + the number of _______________. In fact, the mass number includes the mass of the electrons as well, but because their mass is so __________________ they contribute little to the overall mass. If an atom was the size of a football field, the nucleus would be the size of a _________________. The mass of an atom is therefore condensed into a very small area.

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Question 3 Look at the following nuclide symbols and work out the number of each type of sub-atomic particle.

Question 4 Write the nuclide symbols for the three isotopes of hydrogen: hydrogen-1, hydrogen-2 and hydrogen-3.

Question 5 Define the terms: (a) electron configuration

(b) electron shell

(c) valence shell

(d) valence electron

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Question 6 Write the electron configurations for: (a) magnesium

(b) chlorine

(c) neon

(d) nitrogen

(e) oxygen

(f) lithium

(g) calcium

Question 7 Briefly explain why the noble gases are the least reactive elements on the periodic table.

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Question 8 What is the maximum number of electrons that can fit into each of these shells? (a) 1st (b) 2nd (c) 3rd (d) 4th

Question 9 Complete this table showing some characteristics of the three major sub-atomic particles.

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ANSWER SHEET

STRUCTURE OF THE ATOM

Question 1 Draw a sodium atom with 11 protons, 12 neutrons and 11 electrons. Include a key with your answer.

Question 2 Complete the spaces in these paragraphs using these words. Each word is used once.

mass; 11; protons; small; nucleus; element; electrons; sodium; grape; neutrons sodium The atom I have just drawn is the element ___________________ (Na). Its position on the periodic table is 11 element eleventh, and it has the atomic number __________________. Each ___________________ on the periodic protons table has a different atomic number. This number represents the number of _____________________ an atom of a particular element contains in its nucleus. In a neutral (uncharged) atom, the number of protons = the electrons number of ____________________ .

mass Each atom also has a _________________ number. The mass number represents the number of nucleus particles in the ________________. The mass number represents the number of protons + the number of neutrons _______________. In fact, the mass number includes the mass of the electrons as well, but because their small mass is so __________________ they contribute little to the overall mass. If an atom was the size of a football grape field, the nucleus would be the size of a _________________. The mass of an atom is therefore condensed into a very small area. ELEMENTS, COMPOUNDS AND MIXTURES © 3P Learning

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Question 3 Look at the following nuclide symbols and work out the number of each type of sub-atomic particle.

Question 4 Write the nuclide symbols for the three isotopes of hydrogen: hydrogen-1, hydrogen-2 and hydrogen-3.

Question 5 Define the terms: (a) electron configuration The representation of the electron arrangement in an atom. It shows the distribution of electrons in shells and sub-shells. (b) electron shell Electrons arranged in their quantum energy levels surrounding the nucleus of an atom. (c) valence shell The outermost shell of an atom. (d) valence electron An electron in the outermost shell of an atom which can combine with other atoms. ELEMENTS, COMPOUNDS AND MIXTURES © 3P Learning

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Question 6 Write the electron configurations for: (a) magnesium 2,8,2 (b) chlorine 2,8,7 (c) neon 2,8 (d) nitrogen 2,5 (e) oxygen 2,6 (f) lithium 2,1 (g) calcium 2,8,8,2

Question 7 Briefly explain why the noble gases are the least reactive elements on the periodic table. The noble gases have full outermost electron shells, making them stable. They have no electrons looking to react with other atoms.

Question 8 What is the maximum number of electrons that can fit into each of these shells? (a) 1st 2 (b) 2nd 8 (c) 3rd 18 (d) 4th 32

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Question 9 Complete this table showing some characteristics of the three major sub-atomic particles.

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LESSON GIUDE

INTRODUCTION TO THE PERIODIC TABLE

This activity introduces students to something that is both familiar and unfamiliar to them: the periodic table! Suggested time: 45 minutes Summary of Key Learning Points Students: - learn that elements in the periodic table are arranged in order of atomic number - understand that rows are called periods and columns are called groups - recognise how groups and periods are numbered - identify the number of valence electrons and occupied electron shells based on an element's group and period number - find out that some collections of elements have special names THE PERIODIC TABLE 5 minutes Show students the periodic table and remind them of the definition of 'element'. Element: A pure substance containing atoms that all have the same atomic number (same number of protons in the nucleus). Emphasise that the number of protons is the defining characteristic of an element, though the number of electrons and neutrons may vary. Explain the octaves analogy to students. This analogy was proposed by John Newlands in 1866 when he published his periodic table. It didn't look like today's periodic table because many elements had yet to be discovered. If you use this analogy, the transition metals are skipped. The idea is that each period is like a musical octave. Think of sodium as the middle C note. That would make every group 1 metal a different C note, Group 2 would be D, Group 13 would be E, Group 14 would be F, Group 15 would be G, Group 16 would be A and Group 17 would be B. There is no note for the noble gases in this analogy, but at Newlands' time they hadn't even been discovered. The analogy shows that elements in the same column are similar but not exactly the same. ATOMIC NUMBERS 5 minutes Here a blank periodic table comes up, which the students will slowly fill in by answering a number of questions. The first question to answer relates to the definition of atomic number. Answer: the number of protons in each nucleus (Inquiry point 1) Talking point: The concept of atomic number was discovered by English physicist Henry Moseley in 1913 (who was tragically killed at Gallipoli aged 27). What did earlier versions of the periodic table look like? It is particularly interesting to look at Mendeleev's table, arranged in order of atomic weight.

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ELEMENT SYMBOLS 5 minutes On this page, students write the symbols of 4 elements. Doing this activates all of the element symbols on the table. Make sure students are aware that they must use upper and lower case correctly when writing symbols. This is best done as a class. If you are in a lab, get them to refer to the periodic table on the wall of the lab, or they could refer to the periodic table tool available within IntoScience. Answers: Hydrogen = H Carbon = C Aluminium = Al Gold = Au (Inquiry point 2) Random question: What is the only letter of the alphabet not represented on the periodic table? (Answer = J) ELEMENT GROUPS 5 minutes Explain to students that the groups are the columns in the periodic table. IUPAC, and most of the world, uses group numbering 1 to 18. However, some people still use an older system where the transition metals are not given group numbers. This older system is noted here with Roman numerals. Answer: lithium, sodium, potassium, rubidium, caesium or francium (Inquiry point 3) Talking points: What are the advantages and disadvantages of the different group numbering systems? ELEMENT PERIODS 5 minutes The periods are the rows of the periodic table. It is also the number of occupied electron shells an element has in its ground state. Answer: sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine, argon (Inquiry point 4) Talking point: Which periods do the lanthanides and actinides belong in? METALS, SEMI-METALS AND NON-METALS 5 minutes Students can explore the classification of the elements on this page. Before they select the semi-metals button, get them to guess where they are most likely to find elements with both metallic and non-metallic properties. SPECIAL NAMES 5 minutes Using the drop-down menu allows students to highlight collections of elements that are given special names. This can be done as a class. Research activity: Placing lanthanum and actinium in the d block with the transition elements is controversial. Not all periodic tables do this, but they don't really belong in f block if they have no electrons in f orbitals. This is a good exercise for high-achieving students. Get them to research the case for putting these two elements in d block and the case for placing them in f block. ELEMENTS, COMPOUNDS AND MIXTURES © 3P Learning

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ELEMENT PROPERTIES 5 minutes Selecting a property on the drop-down menu allows it to be displayed under the element symbol on the periodic table. Note that SATP = Standard Ambient Temperature and Pressure. This translates to 25 degrees Celsius and 100 kPa pressure. Electronegativity is measured on the Pauling scale. Talking point: Discuss some of the trends observed here. EXPLORE THE ELEMENTS 5 minutes Learn more about any element by selecting it. You could send students on an element hunt by giving them clues such as, find an element that is used in aeroplanes. Suggested completion levels Basic - Inquiry point goal = 2 Students at this level will: be able to number groups and periods in the periodic table; recognise the significance of the atomic number; identify at least one group with a special name. Core - Inquiry point goal = 3 Students at this level will: be able to number groups and periods in the periodic table; recognise the significance of the atomic number, group number and period number; identify at least three groups with a special name; describe the common properties of at least one group of elements. Advanced - Inquiry point goal = 4 Students at this level will: be able to number groups and periods in the periodic table; recognise the significance of the atomic number, group number and period number; identify all collections of elements that get special names; describe the common properties of at least three groups of elements.

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Question 1 Write the correct element symbol in the box underneath the element's name.

Question 2 Write the names of the elements that match these symbols.

Question 3 What is the name of an element found in air?

Question 4 Which two elements would spell the name of a female chicken if you put their element symbols together?

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Question 5 Name and give the symbol of: (a) the biggest alkali metal

(b) the smallest halogen

(c) a liquid transition metal

(d) the lanthanide named after a continent

(e) the actinide named after the American state where it was discovered

(f) either of the two most recently named elements

(g) the element with 34 protons

(h) the alkaline earth metal starting with C

(i) an element starting with Z

( j) the noble gas named after the Greek word for hidden

(k) the alkali metal that has a name related to the colour red.

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Question 6 Find out the year of discovery and one common use for each of these elements: (a) silver

(b) oxygen

(c) iron

(d) aluminium

(e) uranium

(f) iodine

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Question 1 Write the correct element symbol in the box underneath the element’s name.

Question 2 Write the names of the elements that match these symbols.

Question 3 What is the name of an element found in air? Oxygen

Question 4 Which two elements would spell the name of a female chicken if you put their element symbols together? Helium (He) and Nitrogen (N)

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Question 5 Name and give the symbol of: (a) The biggest alkali metal Francium Fr (b) The smallest halogen Fluorine F (c) A liquid transition metal Mercury Hg (d) The lanthanide named after a continent Europium Eu (e) The actinide named after the American state where it was discovered Californium Cf (f) Either of the two most recently named elements Lawrencium Lr (g) The element with 34 protons Selenium Se (h) The alkaline earth metal starting with C Calcium Ca (i) An element starting with Z Zirconium Zr   or   Zinc   Zn ( j) The noble gas named after the Greek word for hidden Krypton Kr (k) The alkali metal that has a name related to the colour red. Rubidium Rb

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Question 6 Find out the year of discovery and one common use for each of these elements: (a) silver 500BC - Jewellery (b) oxygen 1774 - Mountain climbing (c) iron Ancient times - Tools (d) aluminium 1825 - Foil wrap (e) uranium 1789 - Nuclear reactors (f) iodine 1811 - Disinfectant

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PROPERTIES AND USES OF ELEMENTS

LESSON GUIDE

A meteorite has crashed into the biodome, knocking out the communications satellite on the way through. In this activity, students analyse the meteorite and compare it to known metals and non-metals to try to work out which it is most similar to. In doing so, they learn about general properties of the two different classes of elements. Suggested time: 35 minutes Summary of Key Learning Points Students: - identify that elements can be tested to determine their physical properties - understand non-metals have certain common properties such as low melting points and a dull appearance - learn that metals have common properties such as high density and malleability, and good electrical conductivity - recognise that the properties of an element are related to its possible uses PAGE 1 1 minute Students start by placing the meteorite sample into the sample chamber. METEORITE ANALYSIS 20 minutes On this page, students select a sample to carry out a variety of tests. These are simulated tests, so it would be helpful to explain or demonstrate how these tests might be carried out in the lab. Pressing the play button beside each property will cause the test to be carried out. Students then complete each data panel from the results of the tests. (Inquiry points 1 - 7) It is useful to point out that we are testing physical properties not chemical properties. For appearance, malleability and electrical conductivity, students choose from the drop-down menus. For thermal conductivity, density and melting point, they need to enter the number shown in the test result, but should not add units. RESULTS PAGE 13 minutes Here, students analyse the results of the tests and choose (from the drop-downs menus) which properties belong to metals and which belong to non-metals. Answers: Most metals: are malleable; are lustrous; are good conductors; have high density; have high melting points Most non-metals: are brittle; are dull; are poor conductors; have low density; have low melting points (Inquiry point 8) The meteorite has properties similar to the metals. (Inquiry point 9) Gold (Inquiry point 10) Talking point: How do the properties of the semi-metals compare to those of the metals and non-metals? (Answer = they have some properties in common with metals and some in common with non-metals)

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FINAL PAGE 1 minute All students need to do on this page is answer a simple question correctly then they will be able to launch a new communications satellite! Yes (Inquiry point 11) Talking point: Gold-coated plastic film is used to protect space equipment from intense radiation. Gold is an excellent reflector of radiation, has a very high melting point and is so malleable that incredibly thin layers can be coated on equipment with relative ease. Nearly 41kg of gold was needed to make NASA's Columbia spacecraft. Suggested completion levels Basic - Inquiry point goal = 6 Students at this level will: identify at least two properties of metals and two properties of non-metals; recognise that the use of an element is related to its properties. Core - Inquiry point goal = 9 Students at this level will: identify at least three properties of metals and three properties of non-metals; recognise one property of gold that makes it appropriate for use as a satellite heat shield. Advanced - Inquiry point goal = 11 Students at this level will: identify at least four properties of metals and four properties of non-metals; explain why gold is an appropriate element to use in spacecraft heat shielding; recognise the difference between physical properties and chemical properties.

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PROPERTIES AND USES OF ELEMENTS

WORKSHEET

Question 1 In the table, identify four properties of metals and four properties of non-metals.

Question 2 Silicon is classed as a semi-metal. It is a grey, lustrous solid. It has a very high melting point. It is not malleable and will shatter when hit. Silicon has a relatively low density and has moderate electrical conductivity. Semi-metals have some properties in common with metals and others in common with non-metals. Which of silicon's properties are more like the metals and which are more like non-metals?

Question 3 Label these elements as metals (M) or non-metals (NM). (a) oxygen (b) magnesium (c) tin (d) chlorine (e) uranium

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Question 4 (a) These mystery elements have been tested to determine their properties. See if you can work out if they are metals or non-metals.

Question 5 Elements are (not in order), bromine, zinc, silver, gold and sulfur. Can you work out which is which? A= B= C= D= E=

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PROPERTIES AND USES OF ELEMENTS

ANSWER SHEET

Question 1 In the table, identify four properties of metals and four properties of non-metals.

Question 2 Silicon is classed as a semi-metal. It is a grey, lustrous solid. It has a very high melting point. It is not malleable and will shatter when hit. Silicon has a relatively low density and has moderate electrical conductivity. Semi-metals have some properties in common with metals and others in common with non-metals. Which of silicon's properties are more like the metals and which are more like non-metals? Metals: lustrous, some electrical conductivity; Non-metals: brittle, low density

Question 3 Label these elements as metals (M) or non-metals (NM). (a) oxygen NM (b) magnesium M (c) tin M (d) chlorine NM (e) uranium M

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Question 4 (a) These mystery elements have been tested to determine their properties. See if you can work out if they are metals or non-metals.

Question 5 Elements are (not in order), bromine, zinc, silver, gold and sulfur. Can you work out which is which? A = Silver B = Sulfur C = Gold D = Bromine E = Zinc

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COMPARING COMPOUNDS

LESSON GUIDE

This activity introduces students to covalent and ionic compounds. Suggested time: 45 minutes Summary of Key Learning Points Students: - learn that elements in the periodic table bond in different ways - understand that all compounds may be classed as either ionic compounds or covalent compounds - recognise that ionic compounds are composed of metals and non-metals, while covalent compounds are made of non-metals only - identify salt (sodium chloride) as an example of an ionic compound and sugar (glucose) as an example of a covalent compound - find out that both ionic and covalent bonding are strong types of bonding THE WHITE POWDER MYSTERY 5 minutes That rascally robot Lawrence is causing trouble again. He's left two white powders sitting in the reaction chamber unlabelled. Students will obviously be very familiar with both salt and sugar. Do a brainstorm with the class to work out how you could tell the difference between them. Most will say taste them, but tell them that tasting chemicals is not allowed in the lab, so what else could they do? Suggested answer: Heat the substances. Salt will not melt, but sugar will melt and eventually turn brown. (Inquiry point 1) COMPARING COMPOUNDS 15 minutes Students can test solubility, conductivity and effect of heat on the two white powders. They might not fully understand the significance of the results of all these tests, but it will spark off an interesting class discussion. Emphasise that these tests are all for physical (not chemical) properties. The 'element analysis' test is obviously a simulated 'black box' test. Answers: Heat, conductivity and element analysis showed differences (Inquiry point 2) Yes (Inquiry point 3) Sample A only has non-metals; Sample B has a metal and a non-metal (Inquiry point 4) METALS AND NON-METALS 10 minutes Students play around with trying to bond different elements together. They will find that two metals give an alloy, metal and non-metal produces an ionic compound and two non-metals produce a covalent compound. Talking point: The noble gases are not inclined to react and yet compounds of noble gases exist. How is this possible? (Answer: formation of these unstable compounds is non-spontaneous) Answers: Covalent, Ionic (Inquiry point 5) Glucose = covalent Salt = ionic (Inquiry point 6) Explore this: about noble gases explains the stability of these elements. ELEMENTS, COMPOUNDS AND MIXTURES © 3P Learning

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IONIC AND COVALENT BONDING 5 minutes Again, salt and sugar are used as the compound examples. Selecting an ion on the NaCl model brings up a message telling students that ionic bonding is strong. Pulling two glucose molecules apart is easy, but it is much harder to pull the molecules themselves apart. This reflects the fact that intermolecular bonding is weaker than the covalent bonding holding the molecules together. Answer: Both types of bonding are strong (Inquiry point 7) Talking point: You have discovered that intermolecular bonds are relatively weak. How is this related to the fact that most covalent compounds have low melting points? LABEL POWDERS 5 minutes Hopefully by now students would have worked out that Powder A (on the left) is sugar (Inquiry point 8) and Powder B (on the right) is salt (Inquiry point 9). END PAGE 5 minutes This drag-drop allows students to review what they have learned in this activity. Answers: Covalent compounds: share electrons; relatively low melting points; can be solid, liquid or gas; only made of non-metals. Ionic compounds: relatively high melting points; all solid (normal lab conditions); transfer electrons to form ions; made of metals and non-metals. Both: some dissolve in water; some are white; made of different elements; form crystals. (Inquiry point 10) Suggested completion levels Basic - Inquiry point goal = 6 Students at this level will: recognise the two major types of compounds; identify salt as an ionic compound and sugar as a covalent compound. Core - Inquiry point goal = 8 Students at this level will: describe the two major types of compounds and what they are composed of; explain why salt is classed as ionic and sugar is classed as covalent; identify at least one common physical property of each compound type. Advanced - Inquiry point goal = 10 Students at this level will: describe the two major types of compounds and what they are composed of; explain why salt is classed as ionic and sugar is classed as covalent; explain the results of the physical property tests in this activity in terms of bonding within the compounds.

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COMPARING COMPOUNDS

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Question 1 On the periodic table below: (a) colour in red two elements that would form an ionic compound (b) colour in blue two elements that would make a covalent compound (c) colour in yellow two elements that would form an alloy

Question 2 Identify which of these characteristics would most likely belong to ionic compounds (I) and which would more likely belong to covalent compounds (C). If the characteristic belongs to both, label it (B). (a) Low melting point (b) High melting point (c) Can be solid, liquid or gas at room temperature (d) Can be white (e) Made of metals and non-metals (f) Made of non-metals only (g) Some can dissolve in water (h) Made of ions (i) The atoms share electrons ( j) Has strong bonding ELEMENTS, COMPOUNDS AND MIXTURES © 3P Learning

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Question 3 (a) Identify an element that is very unlikely to ever form a compound.

(b) What is it about this element that makes it so stable (unreactive)?

Question 4 Learning about chemistry is like learning a whole new language! See if you find these terms in the word find below.

covalent, ionic, nonmetal, compound, metal, element, sharing, ions, losing, gaining, electrons

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COMPARING COMPOUNDS

ANSWER SHEET

Question 1 On the periodic table below: (a) colour in red two elements that would form an ionic compound (b) colour in blue two elements that would make a covalent compound (c) colour in yellow two elements that would form an alloy

Question 2 Identify which of these characteristics would most likely belong to ionic compounds (I) and which would more likely belong to covalent compounds (C). If the characteristic belongs to both, label it (B). (a) Low melting point C (b) High melting point I (c) Can be solid, liquid or gas at room temperature C (d) Can be white B (e) Made of metals and non-metals I (f) Made of non-metals only C (g) Some can dissolve in water B (h) Made of ions I (i) The atoms share electrons C ( j) Has strong bonding B ELEMENTS, COMPOUNDS AND MIXTURES © 3P Learning

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ANSWER SHEET

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Question 3 (a) Identify an element that is very unlikely to ever form a compound. Argon (b) What is it about this element that makes it so stable (unreactive)? It is a noble gas and has a full outermost electron shell with eight electrons; it will not giveaway or share electrons easily.

Question 4 Learning about chemistry is like learning a whole new language! See if you find these terms in the word find below.

covalent, ionic, nonmetal, compound, metal, element, sharing, ions, losing, gaining, electrons

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NAMING COMPOUNDS

LESSON GUIDE

Students learn how to name ionic and covalent binary compounds. Suggested time: 45 minutes Summary of Key Learning Points Students: - find out that some compounds have common names that are preferred to the systematic name - discover how to systematically name binary covalent compounds - learn how to name binary ionic compounds DHMO WARNING! 5 minutes The first page introduces chemical nomenclature in a tricky way, but will students be fooled? DHMO is, of course, water. The warning should provide a good starting point for a class discussion. Some may support the ban, while others won't. Their reasons may vary. Answers: No way! (Inquiry point 1) (Reasons will vary) (Inquiry point 2) WHAT'S IN A NAME? 5 minutes Students may not have heard of all the compounds on this page, so it might be helpful to tell them about uses for each of them. Water (H2O): obviously many uses, such as drinking and washing. Peroxide (H2O2) (hydrogen peroxide): bleaching and cleaning agent. Acetylene (C2H2): used as a fuel to produce a high-temperature flame for welding and metal cutting. Nitrous oxide (N2O): laughing gas! Used as a mild anaesthetic and also as an aerosol propellant. Chloroform (CHCl3): used to be used as an anaesthetic, but is now viewed as too dangerous. Major current use is as a precursor to Teflon. (Inquiry point 3 - Correctly matching names and formulas) The 'Explore this' on funny compound names has formulas in short-hand form. Students will need help in understanding the expanded form. Set them the homework task of finding the compound with the silliest name! NAMING BINARY COVALENT COMPOUNDS 10 minutes Talk through the rules then name a few compounds on the board before getting students to try the questions on this page. For example: CO2 = carbon dioxide PF3 = phosphorus trifluoride N2O5 = dinitrogen pentoxide

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LESSON GUIDE

NAMING COMPOUNDS

Answers: N2O = dinitrogen monoxide (common name = nitrous oxide) BCl3 = boron trichloride P2O5 = diphosphorus pentoxide (Inquiry point 4) NAMING IONS AND SIMPLE IONIC COMPOUNDS 10 minutes Make sure students understand what an ion is. The examples on the page are the sodium and oxide ions. It would be helpful to have students draw Bohr representations of the sodium and oxygen atoms (or you could do this on the board) then show how sodium loses its electron and oxygen gains two electrons so that both have a noble gas electron configuration. Remind them that the overall ion charge = number of protons – number of electrons. Have students try naming a few compounds before doing the ones on the page. For example: BaF2 = barium fluoride Na2O = sodium oxide GaBr3 = gallium bromide Answers: Al2O3 = aluminium oxide LiBr = lithium bromide Zn3N2 = zinc nitride (Inquiry point 5) The Science extra on the use of Roman numerals can be used if the students will be naming compounds involving transition metals or group 14 (IV) metals. THE NAME GAME 15 minutes Here, students can play the name game! The aim is to correctly identify compounds as either covalent or ionic, then name all ten before time runs out. They can play the game as many times as they like. They earn one inquiry point on this page. (Inquiry point 6). They need to get the spelling correct to get the questions correct! Suggested completion levels Basic - Inquiry point goal = 2 Students at this level will: recognise at least one compound and its common name; name at least two binary ionic compounds, given their formulas; name at least two binary covalent compounds, given their formulas. Core - Inquiry point goal = 4 Students at this level will: recognise at least two compounds and their common names; name at least four binary ionic compounds, given their formulas; name at least four binary covalent compounds, given their formulas. Advanced - Inquiry point goal = 6 Students at this level will: recognise at least three compounds and their common names; name at least six binary ionic compounds, given their formulas; name at least six binary covalent compounds, given their formulas; write formulas for binary compounds given their names.

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Question 1 Label each of the following substances as either an ionic compound (I), a covalent compound (C) or an element (E). (a) CO2 (b) Ar (c) BaCl2 (d) N2 (e) RbBr (f) H2O (g) SO3 (h) O3 Question 2 Write the correct names for these ionic compounds: (a) MgS

(b) KBr

(c) Ba3N2

(d) Al2O3

(e) NaI

(f) SrF2

(g) Li2S

(h) RaCl2

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NAMING COMPOUNDS

(i) CaO

( j) AlP

Question 3 Write the correct names for these covalent compounds. Remember to use the appropriate prefixes! (a) As4O10

(b) BrO3

(c) BN

(d) N2O3

(e) NI3

(f) SF6

(g) XeF4

(h) PCl3

(i) CO

( j) PCl5

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ANSWER SHEET

Question 1 Label each of the following substances as either an ionic compound (I), a covalent compound (C) or an element (E). (a) CO2 C (b) Ar E (c) BaCl2 I (d) N2 E (e) RbBr I (f) H2O C (g) SO3 C (h) O3 E Question 2 Write the correct names for these ionic compounds (a) MgS magnesium sulfide (b) KBr potassium bromide (c) Ba3N2 barium nitride (d) Al2O3 aluminium oxide (e) NaI sodium iodide (f) SrF2 strontium fluoride (g) Li2S lithium sulfide (h) RaCl2 radium chloride

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ANSWER SHEET

NAMING COMPOUNDS

(i) CaO calcium oxide ( j) AlP aluminium phosphide

Question 3 Write the correct names for these covalent compounds. Remember to use the appropriate prefixes! (a) As4O10 tetraarsenic decoxide (b) BrO3 bromine trioxide (c) BN boron mononitride (d) N2O3 dinitrogen trioxide (e) NI3 nitrogen triiodide (f) SF6 sulfur hexafluoride (g) XeF4 xenon tetrafluoride (h) PCl3 phosphorus trichloride (i) CO carbon monoxide ( j) PCl5 phosphorus pentachloride

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NOTES

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TOPIC SUMMARY: IntoScience topic: Chemical reactions How do you tell if a chemical reaction has taken place? Explore signs and types of chemical reactions.

Description: Chemical change involves substances reacting to form new substances [ACSSU225]

ACTIVITY: PHYSICAL AND CHEMICAL CHANGES There are changes occurring around us all the time. Investigate these everyday situations to work out if they are physical or chemical. Science understanding: identifying the differences between chemical and physical changes [ACSSU225-1] Inquiry skills: Evaluating • Use scientific knowledge and findings from investigations to evaluate claims [ACSIS234] • Deciding whether or not to accept claims based on scientific evidence [ACSIS234-2] ACTIVITY: SIGNS OF CHEMICAL CHANGE What evidence is there that a chemical change has taken place? Identify the five common signs of chemical change. Science understanding: identifying evidence that a chemical change has taken place [ACSSU225-2] Inquiry skills: Questioning and predicting • Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge [ACSIS139] • Using information and knowledge from their own investigations and secondary sources to predict the expected results from an investigation [ACSIS139-3] ACTIVITY: TYPES OF CHEMICAL REACTIONS Investigate common reaction types including synthesis, decomposition, combustion and precipitation. Science understanding: investigating simple reactions such as combining elements to make a compound [ACSSU225-3] Inquiry skills: Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • Drawing conclusions based on a range of evidence including primary and secondary sources [ACSSU145-2] ACTIVITY: LAW OF CONSERVATION OF MASS Discover how the law of conservation of mass applies to every chemical reaction. Science understanding: investigating simple reactions such as combining elements to make a compound [ACSSU225-3] Inquiry skills: Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • Drawing conclusions based on a range of evidence including primary and secondary sources [ACSSU145-2] © 3P Learning

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LESSON GUIDE

PHYSICAL AND CHEMICAL CHANGES

Students learn the differences between physical and chemical changes. Suggested time: 30 minutes Summary of Key Learning Points Students: - find out that physical changes do not involve the formation of any new substances - discover that the formation of at least one new substance always accompanies a chemical change - realise that there are many examples of physical and chemical changes in our everyday lives - understand that many everyday situations, like digestion, involve physical and chemical changes working together to get the job done CHANGES ALL AROUND YOU 5 minutes The first page addresses the idea of a 'new substance'. Make sure that students understand the term means a chemical species that was not there before the change occurred. Answers: (Inquiry point 1) 12 apostles formed by erosion: No new substance formed Coral grows in the Great Barrier Reef: New substance formed PHYSICAL CHANGES 5 minutes Discuss the examples on this page with students. Get them to explain the reasons behind their choices. For example, if they say cooking an egg is a chemical change, see if they can identify the new substances being formed. Answers: (Inquiry point 2) Crumpling paper; Shaping glass; Making a salad Explore this: highlights the fact that any phase change is a physical change, as illustrated by the equation representing ice melting. CHEMICAL CHANGES 5 minutes Similarly to the last page, students identify the chemical changes amongst the examples. Answers: (Inquiry point 3) Digesting food; Iron rusting; Rotting food WORKING TOGETHER 5 minutes This page explores digestion as an example of physical and chemical changes working together. Ask students if they can think of any other examples of situations where both physical and chemical changes are needed to get a job done - there should be plenty! Suggested answers: (Inquiry point 4) Physical change: biting food into smaller pieces Chemical change: stomach acid and enzymes breaking down proteins

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LESSON GUIDE

TRUE OR FALSE? 5 minutes This is a difficult page with some high level concepts. Students might need a bit of extra help to understand the ideas presented here. Answers: (Inquiry point 5) False; False; True PHYSICAL, CHEMICAL OR BOTH? 5 minutes Students check their understanding by labelling six different examples as either physical change, chemical change or both. All labels correct = Inquiry point 6, triggered by selecting 'check' once all correct labels are in place. Writing an explanation for each = Inquiry point 7, triggered by submitting at least 15 characters of text in each text field. Answers: Bite, chew and swallow sandwich = Physical & chemical (Biting food into smaller pieces is physical, but enzymes in saliva breaking down food is chemical) Cordial mixed with water = Physical change (No new substance formed) Butter on toast = Physical change (Melting is a phase change and therefore physical) Petrol burning in a car = Physical & chemical (Petrol being dispersed is physical, but being combusted is chemical as new substances form) Acid rain on statue = Chemical change (A chemical reaction happens so this is a chemical change) Bread dough being kneaded then rising = Physical & chemical (Being kneaded is a physical change, but when it rises a chemical reaction takes place) Suggested completion levels Basic - Inquiry point goal = 3 Students at this level will: define 'physical change' and identify one example; define 'chemical change' and identify one example. Core - Inquiry point goal = 5 Students at this level will: describe the difference between a physical change and a chemical change using examples; identify physical and chemical changes occurring in everyday life. Advanced - Inquiry point goal = 7 Students at this level will: explain how a physical change is different from a chemical change using examples from everyday life; understand that chemical changes always need another chemical change to reverse the process; describe the relationship between chemical bonding and physical and chemical changes.

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PHYSICAL AND CHEMICAL CHANGES

Question 1 Define the terms (a) Physical change

(b) Chemical change

Question 2 Label these changes as either physical changes (P) or chemical changes (C). (a) Sweat evaporates from your skin. _____ (b) A car rusts. _____ (c) Charcoal burns in a furnace. _____ (d) Silver is melted to make jewellery. _____ (e) A cake is cut into pieces. _____ (f) A cake is baked in an oven. _____ (g) Fruit changes colour as it ripens. _____ Question 3 Circle all the words you would associate with physical changes.

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Question 4 Label these statements as true (T) or false (F). (a) Toasting marshmallows is a physical change. _____ (b) Chemical changes are easily reversed. _____ (c) Evaporation is a physical change. _____ (d) A new substance always forms in a physical change. _____ (e) All phase changes are physical changes. _____ (f) Grass growing is a physical change. _____ (g) Milk turning sour is a chemical change. _____ (h) Digestion in humans involves physical changes only. _____ (i) Freezing water to make ice cubes is a physical change. _____ ( j) If a gas is produced, a chemical change must have occurred. _____ (k) Chopping wood into pieces is a chemical change. _____ (l) Fermenting grape juice to make wine is a chemical change. _____ Question 5 Read the following scenarios and decide which type of change is occurring. Provide reasons for your answer.

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Question 1 Define the terms (a) Physical change A change in which no new substance is formed. (b) Chemical change A change in which at least one new substance is formed. Question 2 Label these changes as either physical changes (P) or chemical changes (C). P (a) Sweat evaporates from your skin. _____ C (b) A car rusts. _____ C (c) Charcoal burns in a furnace. _____ P (d) Silver is melted to make jewellery. _____ P (e) A cake is cut into pieces. _____ C (f) A cake is baked in an oven. _____ C (g) Fruit changes colour as it ripens. _____

Question 3 Circle all the words you would associate with physical changes.

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Question 4 Label these statements as true (T) or false (F). F (a) Toasting marshmallows is a physical change. _____ F (b) Chemical changes are easily reversed. _____ T (c) Evaporation is a physical change. _____ F (d) A new substance always forms in a physical change. _____ T (e) All phase changes are physical changes. _____ F (f) Grass growing is a physical change. _____ T (g) Milk turning sour is a chemical change. _____ F (h) Digestion in humans involves physical changes only. _____ T (i) Freezing water to make ice cubes is a physical change. _____ F ( j) If a gas is produced, a chemical change must have occurred. _____ *note: evaporation also produces a gas and that is a physical change. F (k) Chopping wood into pieces is a chemical change. _____ T (l) Fermenting grape juice to make wine is a chemical change. _____ Question 5 Read the following scenarios and decide which type of change is occurring. Provide reasons for your answer.

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SIGNS OF CHEMICAL CHANGE

LESSON GUIDE Students learn about five major signs of chemical change. Suggested time: 45 minutes

Summary of Key Learning Points Students: - find out that there are certain indicators to tell you if a chemical change has occurred or not. - discover that the major signs of chemical change are a gas being released, a temperature change, light released, a precipitate forming or a permanent colour change. - understand that more than one sign of chemical change can occur in the same reaction. CHANGE OR NO CHANGE? 5 minutes On the lab table there are three beakers of chemicals and one larger, empty beaker. Selecting the beakers containing chemicals brings up information about each chemical. The colour coding indicates how dangerous the chemical is to handle. See if students remember their hazard symbols! The reaction shown in the video demonstrates cobalt(II) catalysis of a reaction. The cobalt changes from pink to green as it is oxidized to cobalt(III) then back to pink as the cobalt(III) is reduced to cobalt(II). At the end the mixture looks exactly the same as at the beginning, but along the way it gets very hot and a great deal of gas is released. Chemical change has clearly occurred, however the fact that it looks the same at the beginning and end can be confusing. This shows students that as long as there is at least one sign (e.g. gas released), it doesn't matter if other signs of chemical change (e.g. permanent colour change) are not present. CHEMICAL CHANGE 5 minutes Suggested answers: (Inquiry point 1) The colour changed from pink to green then back to pink. The solution bubbled vigorously. Yes! Quite a few changes were obvious in the solution. CONSTRUCT AN EQUATION 5 minutes Remind students that the substances you start with in a chemical reaction are called the reactants and anything new is a product. Word equations provide a useful shorthand way to show the overall changes happening. By referring to the labels on the chemicals on the first page, students should be able to construct this word equation. Answers: (Inquiry point 2) Hydrogen peroxide + potassium tartrate

potassium methanoate + water + carbon dioxide

Gas produced = carbon dioxide SIGNS OF CHEMICAL CHANGE 10 minutes These videos demonstrate the different signs of change. If students want to look at the word and chemical equations, they can. However, if they find them too confusing, they can leave them hidden and focus on what they are seeing in the videos. Suggested answers: (Inquiry point 3) Burning magnesium: A lot of light is given out.

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LESSON GUIDE

Elephant's toothpaste: A great deal of gas is produced. Decomposing copper(II) carbonate: The solid changes colour from green to black. Making lead(II) iodide: A yellow solid forms in the solution. Hydrochloric acid and sodium hydroxide: The temperature increases but there are no other signs of change. Class activity: Try out these reactions in your school laboratory! FIVE SIGNS 5 minutes Here, students use hints to work out what the five most common signs of change are. Answers: (Inquiry point 4) gas; temperature; precipitate; light; colour Suggested completion levels Basic - Inquiry point goal = 2 Students at this level will: understand what is meant by the term 'chemical change'; identify at least two signs of chemical change. Core - Inquiry point goal = 3 Students at this level will: describe what is meant by the term 'chemical change'; identify at least four signs of chemical change with examples; understand what a precipitate is. Advanced - Inquiry point goal = 4 Students at this level will: explain what is meant by the term 'chemical change'; identify five signs of chemical change with examples; write word equations to describe the reaction examples given; explain what a precipitate is.

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SIGNS OF CHEMICAL CHANGE

Question 1 List 5 common signs of chemical change.

Question 2 For each of these reactions, identify the signs of chemical change you would observe. (a) Birthday candles burn.

(b) Apples ferment to make cider.

(c) Bread goes mouldy.

(d) A car turns rusty.

(e) Fireflies glow at night.

(f) Very old wine has sediment in it.

Question 3 A sealed container of colourless liquid is left on the windowsill of the school laboratory. As the Sun shines on it, condensation is seen gathering on the inside of the container's lid. After several hours, the solution gradually turns yellow and the lid pops off. Explain whether or not these observations were signs of chemical change: (a) Condensation on lid

(b) Liquid turns yellow

(c) Lid pops off

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Question 4 For each of these cases, explain whether or not you think a chemical change has occurred. (a) Perfume from a ten-year-old bottle smells different to the same perfume from a brand new bottle.

(b) An iced tea drink full of ice cubes changes colour slightly over time.

(c) Air has a pungent odour near a working photocopier.

(d) Some sea creatures change colour when startled.

(e) Two clear solutions turn cloudy when mixed.

Question 5 See if you can find all five signs of chemical change in this wordfind!

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Question 1 List 5 common signs of chemical change. Gas produced; permanent colour change; precipitate formed; light produced; temperature change. Question 2 For each of these reactions, identify the signs of chemical change you would observe. (a) Birthday candles burn. Heat and light produced (b) Apples ferment to make cider. Gas produced. (c) Bread goes mouldy. Permanent colour change. (d) A car turns rusty. Permanent colour change; precipitate forms. (e) Fireflies glow at night. Light produced. (f) Very old wine has sediment in it. Precipitate forms. Question 3 A sealed container of colourless liquid is left on the windowsill of the school laboratory. As the Sun shines on it, condensation is seen gathering on the inside of the container's lid. After several hours, the solution gradually turns yellow and the lid pops off. Explain whether or not these observations were signs of chemical change: (a) Condensation on lid This is a physical change because evaporation and condensation are phase changes, which are physical. (b) Liquid turns yellow This is a chemical change because a permanent colour change has occurred. (c) Lid pops off This is a sign of a chemical change because a gas must have been produced, pushing the lid off.

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Question 4 For each of these cases, explain whether or not you think a chemical change has occurred. (a) Perfume from a ten-year-old bottle smells different to the same perfume from a brand new bottle. Yes, a chemical change has occurred. If it smells different, a new substance must have formed. (b) An iced tea drink full of ice cubes changes colour slightly over time. No chemical change has occurred. The melting ice cubes have just diluted the tea. (c) Air has a pungent odour near a working photocopier. A chemical change has occurred and a gas has been produced (ozone). (d) Some sea creatures change colour when startled. No chemical change has occurred; the colour change is not permanent. (e) Two clear solutions turn cloudy when mixed. A chemical change has occurred; a precipitate has formed. Question 5 See if you can find all five signs of chemical change in this wordfind!

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In this activity, students learn about four common reaction types: synthesis; decomposition; combustion and precipitation. If they get the questions correct, more content will be revealed. This means that only students who are able to unlock everything will have all 13 inquiry points available to them. The amount of material unlocked will also affect how long students take to get through the activity. Suggested time: 50 - 60 minutes Summary of Key Learning Points Students: - understand that in a synthesis reaction, two or more substances react to give a single product. - discover that in a decomposition reaction, one substance breaks down into two or more products. - find out that combustion of a fuel is rapid oxidation accompanied by a flame. - observe that a precipitation reaction involves the formation of an insoluble solid. CHEMICAL REACTIONS 5 minutes It's interesting that the most vigorous reactions produce the most benign substances. Get students to choose whether they think the synthesis reaction for sodium chloride will be vigorous or barely noticeable. It would be good to do this as a class and get students to give a reason for their choice. Point out the locations of sodium and chlorine in the periodic table. Does that change what they think? Answer: Extreme reaction SYNTHESIS REACTIONS 10 minutes This page shows an animation of the reaction between hydrogen and chlorine. Make sure that students understand there may be more than two reactants in a synthesis reaction, but there will only ever be one product. The use of the word 'species' in relation to chemical species may also be confusing and could need explanation. Answers: (In order) synthesis; two; reactants; product; reactants; chlorine gas; product; hydrogen chloride gas. (Inquiry point 1) At this point in the activity, students can continue progressing across the pages to get a basic understanding of the different types of reactions, or they can progress to deeper knowledge on each reaction type by completing the 'unlocked' interactives. There are two additional levels beyond the basic knowledge level for each reaction type. Additional content unlocked (for more advanced students). Other students can continue progressing across the pages if they like. Hydrogen + chlorine

hydrogen chloride; 2 ;Oxygen, nitrogen or fluorine (Inquiry point 2)

Additional content unlocked (for even more advanced students). Other students can continue progressing across the pages if they like. H2(g) + Cl2(g) 2HCl(g); Equations that are synthesis reactions: 2H2(g) + O2(g) 2AlN(s); C2H2(g) + Cl2(g) C2H2Cl2(g) (Inquiry point 3)

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2H2O(l); 2Al(s) + N2(g)

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DECOMPOSITION REACTIONS 10 minutes Explain to students that decomposition reactions are essentially the opposite of synthesis reactions. The animation shows methanol decomposing. Answers: The methanol is decomposing into three diatomic molecules, carbon monoxide and two hydrogen molecules. A

B + C; Synthesis (Inquiry point 4)

Additional content unlocked (for more advanced students). Other students can continue progressing across the pages if they like. On both sides (reactants and products) there is 1 carbon atom, 4 hydrogen atoms and 1 oxygen atom (Inquiry point 5) Additional content unlocked (for even more advanced students). Other students can continue progressing across the pages if they like. CH3OH(l)

CO(g) + 2H2(g) (Inquiry point 6)

COMBUSTION REACTIONS 10 minutes This page addresses combustion generally and the combustion of hydrocarbons in particular. In the lab, it is good to show students the combustion of magnesium and ethanol compared to the combustion of methane. It is important that they understand there are many different kinds of fuels, not just hydrocarbons. Answers: Methane; 1. Carbon dioxide 2. Water (Inquiry point 7) Additional content unlocked (for more advanced students). Other students can continue progressing across the pages if they like. Hydrocarbons are C2H6 and C3H8; Per molecule of octane, number of carbon dioxide molecules = 8, number of water molecules = 9. (Inquiry point 8) Additional content unlocked (for even more advanced students). Other students can continue progressing across the pages if they like. 2Mg(s) + O2(g)

2MgO(s);

2C4H7OH(l) + 11O2(g)

8CO2(g) + 8H2O(l) (Inquiry point 9)

PRECIPITATION REACTIONS 10 minutes The animation here shows silver chloride precipitating. Point out to students that the nitrate ions and chloride ions remain in the solution. It would be good to show them a demonstration of this reaction and then compare what they saw to the animation. Answers: Silver chloride (Inquiry point 10) -> silver chloride + sodium nitrate (Inquiry point 11) Correct equation: AgNO3(aq) + NaCl(aq)

AgCl(s) + NaNO3(aq) (Inquiry point 12)

Missing things (in order): barium sulfate; NaCl; lithium chloride; zinc sulfide; sodium chloride (Inquiry point 13) CHEMICAL REACTIONS © 3P Learning

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MATCH THE REACTIONS 5 minutes Answers: Video 1: Decomposition Video 2: Precipitation Video 3: Synthesis and combustion Suggested completion levels Basic - Inquiry point goal = 5 Students at this level will: be able to recognise examples of synthesis, decomposition, combustion and precipitation reactions. Core - Inquiry point goal = 9 Students at this level will: describe synthesis, decomposition, combustion and precipitation reactions; give the general reaction equation for each of these four reaction types; recognise examples of these reactions from observations, animations or equations. Advanced - Inquiry point goal = 13 Students at this level will: explain the characteristics of synthesis, decomposition, combustion and precipitation reactions using examples; give the general reaction equation for each of these four types as well as a specific equation example; complete word and chemical equations; identify what a hydrocarbon is.

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Question 1 Label these general reaction types as either synthesis, decomposition, combustion or precipitation. (a) hydrocarbon + oxygen

(b) A

carbon dioxide + water

B+C

(c) AB(aq) + CD(aq)

(d) A + B

AD(s) + BC(aq)

C

Question 2 Here are the word equations of five different reactions. Label the reaction type shown. Some reactions may fit more than one reaction type. (a) sodium chloride + silver nitrate

(b) methane + oxygen

carbon dioxide + water

(c) magnesium + oxygen

(d) carbon dioxide

(e) ethene + chlorine

silver chloride(s) + sodium nitrate

magnesium oxide

carbon + oxygen

1,2-dichloroethane

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WORKSHEET Question 3 Which reaction type fits each of these chemical equations? (a) 2CH3OH(l) + 3O2(g)

2CO2(g) + 4H2O(l)

(b) Ba(NO3)2(aq) + Na2SO4(aq)

(c) 2NI3(s)

BaSO4(s) + 2NaNO3(aq)

N2(g) + 3I2(s)

(d) 2Li(s) + F2(g)

2LiF(s)

(e) C4H8(g) + 6O2(g)

4CO2(g) + 4H2O(l)

Question 4 Explain: (a) how a synthesis reaction is different to a decomposition reaction.

(b) how you could recognise a combustion reaction taking place.

(c) how you know when precipitation is occurring.

(d) which reactant appears in all combustion reactions.

(e) how a reaction might fit more than one category.

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Question 5 A hydrocarbon burns completely to produce carbon dioxide and water. One molecule of the hydrocarbon produces 7 molecules of carbon dioxide and 8 molecules of water. (a) What is a hydrocarbon?

(b) What is the chemical formula of the hydrocarbon? Explain how you worked it out.

  Question 6 There are 6 reaction types hidden in this word find. Can you find them all? There might even be a secret message in there somewhere.

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ANSWER SHEET Question 1

Label these general reaction types as either synthesis, decomposition, combustion or precipitation. (a) hydrocarbon + oxygen

carbon dioxide + water

Combustion (b) A

B+C

Decomposition (c) AB(aq) + CD(aq)

AD(s) + BC(aq)

Precipitation (d) A + B

C

Synthesis Question 2 Here are the word equations of five different reactions. Label the reaction type shown. Some reactions may fit more than one reaction type. (a) sodium chloride + silver nitrate

silver chloride(s) + sodium nitrate

Precipitation (b) methane + oxygen

carbon dioxide + water

Combustion (c) magnesium + oxygen

magnesium oxide

Combustion; synthesis (d) carbon dioxide

carbon + oxygen

Decomposition (e) ethene + chlorine Synthesis

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1,2-dichloroethane

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Question 3 Which reaction type fits each of these chemical equations? (a) 2CH3OH(l) + 3O2(g)

2CO2(g) + 4H2O(l)

Combustion (b) Ba(NO3)2(aq) + Na2SO4(aq)

BaSO4(s) + 2NaNO3(aq)

Precipitation (c) 2NI3(s)

N2(g) + 3I2(s)

Decomposition (d) 2Li(s) + F2(g)

2LiF(s)

Synthesis (e) C4H8(g) + 6O2(g)

4CO2(g) + 4H2O(l)

Combustion

Question 4 Explain: (a) how a synthesis reaction is different to a decomposition reaction. In a synthesis reaction there is only one product, but in a decomposition reaction there is always more than one product. (b) how you could recognise a combustion reaction taking place. Oxygen is always a reactant and you can always see a flame. (c) how you know when precipitation is occurring. Cloudiness is observed when two clear solutions are mixed. (d) which reactant appears in all combustion reactions. Oxygen is always a reactant. This can be proven by trying to burn something in the absence of oxygen. (e) how a reaction might fit more than one category. Many reactions can fit into multiple categories. For example, when a reactive metal burns in oxygen to produce the metal oxide, it is both a combustion and synthesis reaction. 

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Question 5 A hydrocarbon burns completely to produce carbon dioxide and water. One molecule of the hydrocarbon produces 7 molecules of carbon dioxide and 8 molecules of water. (a) What is a hydrocarbon? A compound made only of hydrogen and carbon. (b) What is the chemical formula of the hydrocarbon? Explain how you worked it out. C7H16 Each carbon dioxide has 1 carbon atom so it must be C7. Each water has two hydrogens so it is H16.  Question 6 There are 6 reaction types hidden in this word find. Can you find them all? There might even be a secret message in there somewhere.

Secret message: Chemistry is awesome!

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LESSON GUIDE

Students can learn about the Law of Conservation of Mass within the context of an experiment first performed by French chemist Antoine Lavoisier in the 1700s. Suggested time: 20 minutes Summary of Key Learning Points Students: - conduct an experiment to demonstrate the Law of Conservation of Mass - understand that in any chemical reaction, the mass of the reactants will be equal to the mass of the products - observe how balancing equations relates to conservation of mass THE BELL JAR EXPERIMENT 5 minutes In this simulated experiment, mercury is burned in air. You might want to point out that we would not do this experiment in real life with the given apparatus as it would not be safe and the bell jar would not be sealed. For this experiment we must assume that when the bell jar is placed on the hot plate, a perfect seal is formed and no air can get in or out for the duration of the experiment. Answers: (Inquiry point 1) Mass of element (g) = 2.00 Mass (bell jar + element) (g) = 642.00 Final mass after heating (g): 642.00 Mass of product (g): 2.16 LAVOISIER AND THE LAW OF CONSERVATION OF MASS 10 minutes Discuss the experiment with students, reminding them that air is about 78% nitrogen and 21% oxygen. The nitrogen tends to be unreactive in most instances. Mercury combines with oxygen, producing mercury(II) ions and oxide ions. Obviously when Lavoisier did this reaction he had quite different apparatus. For simplicity, we have used a combination hot plate/balance. The picture below was drawn by Madame Lavoisier. Using this, Lavoisier was able to burn mercury in the swanshaped flask and noted that the level of air in the bell jar went down by about a fifth. This makes sense when you consider that air is about one fifth oxygen.

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LAW OF CONSERVATION OF MASS

Answers: (Inquiry point 2) Greater than Equal to Discussion point 1: How would the composition, pressure and mass of the air in the bell jar after the reaction compare to the air before the reaction? (Answer = there would be less oxygen, less mass and reduced pressure) Discussion point 2: If you were going to replicate Lavoisier's experiment in the school laboratory, how would you do it? There could be many answers to this question! REARRANGING ATOMS 5 minutes The idea of this page is to show students what conservation of mass means on a molecular level. The product of the mercury reaction is an ionic compound, so only a small portion of the ionic cluster is shown. Students must balance the equation by adding mercury atoms and oxygen molecules to the reactant side. Answer: (Inquiry point 3) 2 x mercury atoms, 1 x oxygen molecule Discussion point: Why is the mercury atom larger than the mercury(II) ion? (Answer = as an ion it has lost its 6th shell electrons). Why is the oxygen atom smaller than the oxide ion? (Answer = with extra electrons added to the second shell, electron-electron repulsion increases and the shell expands) Make sure students understand the relationship between the 3D equation model, the word equation and the chemical equation. Emphasise the point that chemical equations must be balanced to reflect the Law of Conservation of Mass. Suggested completion levels Basic - Inquiry point goal = 1 Students at this level will: state the Law of Conservation of Mass. Core - Inquiry point goal = 2 Students at this level will: explain how the Law of Conservation of Mass relates to chemical reactions; describe the relationship between conservation of mass and balancing equations. Advanced - Inquiry point goal = 3 Students at this level will: use an example to explain the Law of Conservation of Mass; describe what conservation of mass means on a molecular level; evaluate the importance of balancing chemical equations.

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Question 1 State the Law of Conservation of Mass.

Question 2 On a chilly Parisian morning back in 1780, Antoine Lavoisier burned 3.06 g of mercury in air. He found that the product of the reaction, an orange powder, weighed 3.30 g. (i) Which component of air did mercury react with?

(ii) Write the word equation for this reaction, given that the product is mercury(II) oxide.

(iii) Write the balanced chemical equation for this reaction.

(iv) Explain how the Law of Conservation of Mass is upheld in this reaction.

(v) Lavoisier then decomposed the mercury(II) oxide product using heat and a reducing atmosphere. What mass of mercury and oxygen would he have obtained if he decomposed the product back into its constituent elements?

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WORKSHEET Question 3

The thermite reaction is a spectacular reaction that releases a great deal of heat. The word and chemical equations for the reaction are: aluminium + iron(III) oxide 2Al(s) + Fe2O3(s)

iron + aluminium oxide 2Fe(s) + Al2O3(s)

An adventurous student carried this dangerous reaction out a number of times and measured the masses of reactants and products. Fill in the missing values in their results table.

Question 4 The Law of Conservation of Mass tells us that we must balance chemical equations so that there are the same number of each type of atom on both the reactants and products sides. See if you can balance these chemical equations by adding the correct coefficients in front of the chemical formulas. The first one has been completed for you. Remember that there is no need to add a 1 if only one of that species is needed. (a) 2Mg(s) + O2(g) (b) Na(s) + Cl2(g)

2MgO(s) NaCl(s)

(c) HCl(aq) + Na2CO3(s) (d) Cu(s) + AgNO3(aq) (e) C2H6(g) + O2(g)

Ag(s) + Cu(NO3)2(aq) CO2(g) + H2O(l)Question 1

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NaCl(aq) + H2O(l) + CO2(g)

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ANSWER SHEET

Question 1 State the Law of Conservation of Mass. Matter is neither created or destroyed in chemical reactions. This means that the mass of the reactants always equals the mass of the products. Question 2 On a chilly Parisian morning back in 1780, Antoine Lavoisier burned 3.06 g of mercury in air. He found that the product of the reaction, an orange powder, weighed 3.30 g. (i) Which component of air did mercury react with? Oxygen (ii) Write the word equation for this reaction, given that the product is mercury(II) oxide. mercury + oxygen

mercury (II) oxide

(iii) Write the balanced chemical equation for this reaction. 2Hg(l) + O2(g)

2HgO(s)

(iv) Explain how the Law of Conservation of Mass is upheld in this reaction. The mass of the mercury and oxygen that reacts is equal to the mass of the mercury(II) oxide produced. (v) Lavoisier then decomposed the mercury(II) oxide product using heat and a reducing atmosphere. What mass of mercury and oxygen would he have obtained if he decomposed the product back into its constituent elements? Mercury = 3.06g ; mass of oxygen = 3.30 - 3.06 = 0.24g

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ANSWER SHEET Question 3

The thermite reaction is a spectacular reaction that releases a great deal of heat. The word and chemical equations for the reaction are: aluminium + iron(III) oxide 2Al(s) + Fe2O3(s)

iron + aluminium oxide 2Fe(s) + Al2O3(s)

An adventurous student carried this dangerous reaction out a number of times and measured the masses of reactants and products. Fill in the missing values in their results table.

Question 4 The Law of Conservation of Mass tells us that we must balance chemical equations so that there are the same number of each type of atom on both the reactants and products sides. See if you can balance these chemical equations by adding the correct coefficients in front of the chemical formulas. The first one has been completed for you. Remember that there is no need to add a 1 if only one of that species is needed. (a) 2Mg(s) + O2(g) -> 2MgO(s) (b) 2Na(s) + Cl2(g)

2NaCl(s)

(c) 2HCl(aq) + Na2CO3(s) (d) Cu(s) + 2AgNO3(aq) (e) 2C2H6(g) + 7O2(g)

CHEMICAL REACTIONS © 3P Learning

2NaCl(aq) + H2O(l) + CO2(g) 2Ag(s) + Cu(NO3)2(aq)

4CO2(g) + 6H2O(l)

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CHEMICAL SCIENCES [ACSSU151]

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TOPIC SUMMARY: IntoScience topic: States of matter Investigate solids, liquids and gases and explore The Particle Model of Matter

Description: The properties of the different states of matter can be explained in terms of the motion and arrangement of particles [ACSSU151]

ACTIVITY: PARTICLE MATTERS Investigate how particles move in solids, liquids and gases at the Particle Party! Get to know the Particle Model of Matter. Elaboration: modelling the arrangement of particles in solids, liquids and gases [ACSSU151-2] Inquiry skills: Questioning and predicting • Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge [ACSIS139] • using information and knowledge from their own investigations and secondary sources to predict the expected results from an investigation [ACSIS139-3] Processing and Analysing Data and Information • Construct and use a range of representations, including graphs, keys and models to represent and analyse patterns or relationships, including using digital technologies as appropriate [ACSIS144] • explaining the strengths and limitations of representations such as physical models, diagrams and simulations in terms of the attributes of systems included or not included [ACSSU144-2] •

Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • drawing conclusions based on a range of evidence including primary and secondary sources [ACSSU145-2]

General capabilities: Critical and Creative Thinking ACTIVITY: COMPRESSING MATTER Can you compress solids, liquids or gases? What if they are heated or cooled? Use this syringe demonstration for a deeper understanding of matter. Elaboration: modelling the arrangement of particles in solids, liquids and gases [ACSSU151-2] Inquiry skills: Questioning and predicting • Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge [ACSIS139] • using information and knowledge from their own investigations and secondary sources to predict the expected results from an investigation [ACSIS139-3] Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • drawing conclusions based on a range of evidence including primary and secondary sources [ACSSU145-2] General capabilities: Critical and Creative Thinking © 3P Learning

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ACTIVITY: CHANGING STATES Delve into how solids, liquids and gases can change state. Observe particle views of these processes and some global examples. Elaboration: modelling the arrangement of particles in solids, liquids and gases [ACSSU151-2] Inquiry skills: Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • constructing tables, graphs, keys and models to represent relationships and trends in collected data [ACSSU145-1] • drawing conclusions based on a range of evidence including primary and secondary sources [ACSSU145-2] ACTIVITY: DIFFUSION IN THE LAB These colourful lab experiment videos investigate the phenomenon of diffusion. Understand how temperature affects particle energy and the rate of diffusion. Elaboration: using the particle model to explain observed phenomena linking the energy of particles to temperature changes [ACSSU151-3] Inquiry skills: Questioning and predicting • Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge [ACSIS139] • using information and knowledge from their own investigations and secondary sources to predict the expected results from an investigation [ACSIS139-3] Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • drawing conclusions based on a range of evidence including primary and secondary sources [ACSSU145-2] ACTIVITY: EXPANSION EXPERIMENTS These experiments demonstrate expansion of solids, liquids and gases when heated. Can you help explain this? Elaboration: using the particle model to explain observed phenomena linking the energy of particles to temperature changes [ACSSU151-3] Inquiry skills: Questioning and predicting • Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge [ACSIS139] • using information and knowledge from their own investigations and secondary sources to predict the expected results from an investigation [ACSIS139-3] ACTIVITY: THE PARTICLE MODEL EXAMINER The Particle Model Examiner reports some strange occurrences resulting from a recent heatwave. Can you help explain what’s happening? Elaboration: using the particle model to explain observed phenomena linking the energy of particles to temperature changes [ACSSU151-3]

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Inquiry skills: Processing and Analysing Data and Information • Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions [ACSIS145] • drawing conclusions based on a range of evidence including primary and secondary sources [ACSSU145-2] Evaluating • Use scientific knowledge and findings from investigations to evaluate claims [ACSIS234] • identifying the scientific evidence available to evaluate claims [ACSIS234-1] Communicating • Communicate ideas, findings and solutions to problems using scientific language and representations using digital technologies as appropriate [ACSIS148] • selecting and using appropriate language and representations to communicate science ideas within a specified text type and for a specified audience [ACSIS148-2] General capabilities: Critical and Creative Thinking ACTIVITY: USING MODELS IN SCIENCE Models represent reality and can be useful in science. Investigate how and why scientific models are used. Elaboration: explaining why a model for the structure of matter is needed [ACSSU151-1] Inquiry skills: Processing and Analysing Data and Information • Construct and use a range of representations, including graphs, keys and models to represent and analyse patterns or relationships, including using digital technologies as appropriate [ACSIS144] • explaining the strengths and limitations of representations such as physical models, diagrams and simulations in terms of the attributes of systems included or not included [ACSSU144-2]

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PARTICLE MATTERS

Students investigate the nature of matter and are introduced to the Particle Model of Matter by exploring a party scene. This activity employs a number of 'particle view' exercises that allow students to visualise a simplified model of the arrangement of particles in solids, liquids and gases. Suggested time: 45 minutes Summary of Key Learning Points Students: - observe that altering temperature changes the pressure of gases - understand that everything with mass is made of particles - discover that the particles in matter are always moving - find out that the different states of matter have different properties - accept that the Particle Model of Matter is a simplification that allows them to visualize something too small to be seen PARTICLE MATTERS 10 minutes To start, students watch a video showing liquid nitrogen being poured onto a balloon. They are not expected to give a full explanation at this stage, but should be encouraged to offer ideas about why the balloon shrank in extreme cold. Point out to students the safety equipment needed when handling liquid nitrogen. Example answer: The air inside the balloon liquefies when the liquid nitrogen is poured onto it, which makes the balloon shrink. (Inquiry point 1) Extension: Review the composition of air (78% nitrogen, 21% oxygen plus smaller quantities of water, argon, carbon dioxide and other gases) and the concept of pressure being caused by collisions of the gas molecules with the walls of the container. Students are then asked to predict what will happen when the balloon warms back up again. Answer: Expand to its previous shape. (Inquiry point 2) Talking point: There is frost visible on the outside of the balloon. Ask students where this came from. It is caused by water in the air crystallising on the outside of the balloon. THE PARTICLE PARTY 15 minutes Students explore the objects at the party using particle view boxes activated by selecting the objects and see that there are only three states of matter present. They explain the differences between two of the party objects at the particle level. Ask them to look around the room they are in and think about the particle movement in the objects nearby. Explain that the pressure they experience is due to air molecules colliding with their skin. Give an example of something that is not made of particles, such as light. Use the Explore this to start a conversation about the nature of particles in different types of matter. Example answer: The particles in the present stay in the same position and vibrate, but the particles in the cordial move a lot faster and are not in fixed positions. (Inquiry point 3) Classroom demonstration: Draw a smiley face on a pink marshmallow and put it in a bell jar attached to a vacuum pump. Tell them that it is their brain while climbing Everest. Sucking the air out reduces pressure causing the marshmallow to swell. This helps students understand the concept of pressure. Discuss altitude sickness and the fact that water boils at a lower temperature at high altitude. Talking point: This is a good time to start exploring the pros and cons of the Particle Model. After this, students label the objects as solid, liquid or gas. (Inquiry point 4) STATES OF MATTER © 3P Learning

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PARTICLE MATTERS

LESSON GUIDE

Solids: present, polystyrene cup, table, spoon, cake, jelly, chair, glass Liquids: cordial, milk Gases: air, helium It isn't always easy to classify matter as solid, liquid or gas. From the objects at the party, the jelly and Styrofoam were the trickiest. Many colloids are hard to classify, including toothpaste and smog. Grey matters: Is glass a solid or a liquid? MOVEMENT AND ENERGY 10 minutes Students select three different objects (spoon, cordial, balloon) to view the objects at the particle level and manipulate the temperature using a slider to see that particles move faster when hotter and slower when cooler. Solid answers: faster/quicker; liquid (Inquiry points 5, 6) Liquid answers: quickly; gas (Inquiry points 7, 8) Gas answers: decreases; more (Inquiry points 9, 10) Talking point: Introduce the idea of expansion and contraction with changing temperature. Sometimes scientists have to balance temperature and pressure considerations, like when they launch an ozonesonde. The helium balloon is only partially filled at ground level to allow for expansion at high altitude, which occurs despite the lower temperatures with increasing altitude. WHAT DEFINES EACH STATE? 5 minutes After exploring how particle movement changes with changing temperature and reading about the properties of solids, liquids and gases, students consolidate their understanding by dragging the properties to the correct column in the table. Although liquids cannot be compressed in a school lab setting, they are listed as 'little compression' since they could be compressed slightly if the pressure was high enough. Solid: fixed shape; constant volume; high density; cannot be compressed; does not flow Liquid: no fixed shape; constant volume; moderately high density; little compression; flows easily Gas: no fixed shape; expands to fill container; low density; easily compressed; flows easily (Inquiry point 11) Talking point: Use the Science Extra to start a discussion about other states of matter. Plasma is a particularly important one to mention. Another point to talk about is bonding in the different states. This is tricky to discuss since there is such a wide range of bonding strengths within the different states. Talking about the one substance though, the bonding in the solid will be stronger than that in the liquid. In the gas state the particles are not bonded to each other, although attraction forces can come into play when they collide. PARTICLE MODEL OF MATTER 5 minutes The next page states the two major tenets of the Particle Model of Matter. Students should be introduced briefly to the reasons for using scientific models. They should also understand that models can change over time as new information comes to light that contradicts existing models. The development of the model of the atom is a good example of this. At the end of this activity, students are asked to write a new explanation for the shrinking balloon, this time in terms of particles. STATES OF MATTER © 3P Learning

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Example answer: When the nitrogen is poured onto the balloon, the gas particles inside move more slowly, and eventually come together to form a liquid. Less gas molecules hit the inside walls of the balloon so the pressure inside the balloon drops, causing the higher air pressure outside the balloon to squash it until pressure inside = pressure outside. (Inquiry point 12) Classroom demonstration: Put a small volume of water in an aluminium can and heat it over a Bunsen burner. When the water is boiling, invert the can into a container of half ice and half cold water. The can crushes due to the dramatic drop in pressure inside the can when the steam condenses. Suggested completion levels Basic - Inquiry point goal = 4 Students at this level will: recognise that all matter is made of particles; identify the three common states of matter; state at least one property of each state of matter. Core - Inquiry point goal = 8 Students at this level will: recognise that all matter is made of particles which are constantly moving; identify the three common states of matter; state at least three properties of each state of matter; draw the arrangement of particles in each state of matter; understand that matter has mass and takes up space. Advanced - Inquiry point goal = 12 Students at this level will: recognise that all matter is made of particles which are constantly moving; identify the three common states of matter; state at least four properties of each state of matter; draw the arrangement of particles in each state of matter; understand that matter has mass and takes up space; relate the structure of matter to its density.

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Question 1 Here is a bottle filled with honey:

In the first box below, draw what the particles look like in the glass. In the second box, draw what the particles look like in the honey. In the third box, draw what the particles look like in the air above the honey in the bottle.

Question 2 In each column of the table, identify TWO characteristics of each physical state.

Question 3 Write the word that best matches the description. The first letter of each word has been given. (a) A substance that has widely-spaced particles. G__ (b) Gases and liquids can do this, but solids can't. F___ (c) A state in which the particles vibrate in fixed positions. S____ STATES OF MATTER © 3P Learning

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(d) It is easy to do this to a gas. C_______ (e) This state of matter has disorderly particles and quite high density. L_____ (f) Particles move faster when they have more of this. E_____

Question 4 Explain the following: (a) Solids can't be compressed.

(b) A balloon full of air will shrink if you put it in a freezer.

(c) Liquids don't have a fixed shape.

Question 5 Find these words in the puzzle and outline or highlight them.

Solid, liquid, gas, compress, energy, density, vibrate, pressure, expand, contract

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Question 1 Here is a bottle filled with honey:

In the first box below, draw what the particles look like in the glass. In the second box, draw what the particles look like in the honey. In the third box, draw what the particles look like in the air above the honey in the bottle.

Question 2 In each column of the table, identify TWO characteristics of each physical state.

Question 3 Write the word that best matches the description. The first letter of each word has been given. (a) A substance that has widely-spaced particles. GAS (b) Gases and liquids can do this, but solids can't. FLOW (c) A state in which the particles vibrate in fixed positions. SOLID STATES OF MATTER © 3P Learning

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(d) It is easy to do this to a gas. COMPRESS (e) This state of matter has disorderly particles and quite high density. LIQUID (f) Particles move faster when they have more of this. ENERGY Question 4 Explain the following: (a) Solids can't be compressed. There is no room between the particles to allow for squashing. (b) A balloon full of air will shrink if you put it in a freezer. When the air cools it condenses, turning into a liquid. Pressure is lowered and the balloon shrinks. (c) Liquids don't have a fixed shape. The particles are disorderly and flow easily. Question 5 Find these words in the puzzle and outline or highlight them.

Solid, liquid, gas, compress, energy, density, vibrate, pressure, expand, contract

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COMPRESSING MATTER

LESSON GUIDE

Students explore the compressibility of solids, liquids and gases by using interactive syringes. They also look at solid, liquid-filled and air-filled tyres to relate the compressibility of matter to real-world applications. Suggested time: 45 minutes Summary of Key Learning Points Students: - understand that the three common states of matter have different degrees of compressibility - observe that the plunger movement on syringes can be related to the compressibility of the substance inside - find out that gases exert pressure - discover that heating substances in closed systems makes them harder to compress - predict the compressibility of solid, liquids and gases based on their observations COMPRESSING MATTER 7 minutes The activity starts with a view of three different types of tyres. Air-filled (pneumatic) tyres are the most common type. Solid rubber tyres would only be found on small vehicles like golf carts and ride-on mowers. Liquid-filled tyres are commonly used in tractors to provide a bit of stability and prevent them from tipping over. Point out to students where these tyres are commonly used then let them order them from hardest to easiest to squash. Answer (hardest to easiest): Solid rubber, liquid-filled, air-filled (Inquiry point 1) Remind students what the arrangement of particles looks like in each of the three common states of matter. Relate the amount of space between adjacent particles to how easy or difficult a substance is to squash. This would also be a good place to review the concept of density. Talking point: Formula 1 tyres are filled with a nitrogen-rich mixture as this helps maintain tyre pressure better. Nitrogen has an atomic radius of 56pm while oxygen's is 48pm. How does this relate to tyre pressure? SOLIDS, LIQUIDS AND GASES 15 minutes A common laboratory experiment is to try to compress sealed syringes filled with (respectively) a solid, a liquid and a gas. This experiment is simulated here. Before students try to depress the plungers, get them to predict which syringe (solid-filled, liquid-filled or gas-filled) would be easier to compress and why. Note that in this simulation it is possible to compress the liquid slightly, but that would not be possible in the school laboratory as it would take too much force and require a tough, perfectly-sealed syringe. Answers (top to bottom): No compression, almost no compression, compresses easily. (Inquiry point 2) Solid, liquid, gas (Inquiry point 3) The major problem with trying to do this experiment in a laboratory is keeping the syringes sealed once the plungers are depressed. With your average plastic syringe, this tends not to work so well, although this could be attempted as a demonstration. Talking point: What is the difference in density between a solid and a liquid? Try this calculation: solid mercury has a density of 14.10g/mL and liquid mercury has a density of 13.53g/mL. If the solid arrangement represents the closest the particles can get, what volume decrease would it take for 20mL of liquid mercury to get into that arrangement? In other words, what is the maximum theoretical compression possible for 20mL of liquid mercury? (Answer = 20 - ((13.53 x 20)/14.10) = 0.81mL) INCREASING PRESSURE 5 minutes Revise the concept of pressure. Pressure = force/area. As area decreases (for example when pushing a plunger in), force increases. If students have ever used a hand pump to fill any air-filled object (like a bike tyre, an air mattress or a football), they would notice that it gets harder the closer the object comes to being filled. STATES OF MATTER © 3P Learning

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Example answer: As the tyre becomes increasingly filled with air, the pressure increases. This is because there are more particles colliding with the inner walls of the tyre. This creates a 'push' that makes it harder to put more air in. HEATING AND COOLING 10 minutes In the 'Heating and cooling' section students predict whether the plungers become harder or easier to push when the syringes are heated or cooled. Remind them that heating increases the kinetic energy of the particles. Answers: Harder (heated), easier (cooled) (Inquiry point 4) After making their predictions, students then have the ability to heat and cool the syringes using a slider. When they are heated, you will notice the plunger moving out on the gas syringe in particular (and the liquid one very slightly). This is because an increase in temperature causes an increase in gas volume (in accordance with Charles' law). The converse case happens when the syringes are cooled. Students should notice that more effort is needed to push the plungers when heated compared to when they are cooled. Even with the decrease in volume that occurs with cooling, this effort relationship still holds true. Example answer: Yes, my predictions were correct. It is harder to push the plungers when hot and easier when cool. (Inquiry point 5) CLOSING IN ON COMPRESSIBILITY 5 minutes Students complete two drag drops to summarise what they have learned. Drag drop answers (left to right): Solid, liquid, gas (Inquiry point 6) Decreases, no change, increases (Inquiry point 7) COMPRESSING CAR TYRES 2 minutes Students then choose the correct tyre for each vehicle. Answers: Car = air-filled tyres Golf cart = solid rubber tyres Tractor = liquid-filled tyres (Inquiry point 8) Suggested completion levels Basic - Inquiry point goal = 4 Students at this level will: identify the meaning of the term 'compress'; recognise that solids, liquids and gases vary in their ability to be compressed; observe that the degree of compression possible depends on the spacing of the particles in a substance. Core - Inquiry point goal = 6 Students at this level will: describe the meaning of the term 'compress'; understand that solids, liquids and gases vary in their ability to be compressed; account for the degree of compression possible in terms of the spacing of the particles in a substance; describe the resistance to gas compression in terms of pressure. Advanced - Inquiry point goal = 8 Students at this level will: describe the meaning of the term 'compress'; explain that solids, liquids and gases vary in their ability to be compressed; account for the degree of compression possible in terms of the spacing of the particles in a substance; describe the resistance to gas compression in terms of pressure; explain why heating makes it harder to compress matter and cooling makes it easier. STATES OF MATTER © 3P Learning

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CHANGING STATES

LESSON GUIDE

In this activity, students learn how changes of state can occur through the addition or removal of heat energy, and become familiar with the terminology involved. Suggested time: 45 minutes Summary of Key Learning Points Students: - understand that examples of changes of state are all around us - find out that melting is a change of state from solid to liquid, and freezing is the opposite process - discover that evaporation is a change of state from liquid to gas, and condensation is the opposite process - learn that sublimation is a change of state from solid to gas - observe that a change of state diagram can be used to summarise state changes CHANGING STATES 5 minutes Students watch the videos and write a one-sentence description for each. Get them to brainstorm where other changes of state commonly occur. Which changes of state do they observe in their daily lives? Answers: The kettle is boiling. The ice block is melting. The iron is melting. The ice block and iron are undergoing the same process (melting) (Videos 2 and 3) (Inquiry point 1) MELTING AND FREEZING 10 minutes Melting is a change of state from solid to liquid. The example given is the melting of polar ice, which is blamed for rising sea levels. Explain to students that melting happens at the melting point, also called the freezing point. Pressure has little effect on melting point. It is good to relate these phase changes to the arrangement of the particles. Explain that when something melts, the particles go from a rigid arrangement to a free-moving but still densely packed arrangement. This is shown in the particle view animations, which show melting on the left and freezing on the right. Answers: Freezing (Inquiry point 2) Melting (on left), freezing (on right) (Inquiry point 3) Antarctica (Inquiry point 4) Melting ice can cause sea levels to rise because as ice part of the volume is above the water line. Talking points: What proportion of the polar ice caps have already melted in the current period of global warming? Why do some people say climate change is a hoax? Briefly discuss the energy involved in phase changes. To turn a solid to a liquid, the bonds between particles must be weakened. During a phase change, a flat section is observed in heating curves because the energy going into the substance is being used to break or weaken bonds, and does not increase the kinetic energy and hence the temperature of the substance.

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LESSON GUIDE

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EVAPORATION AND CONDENSATION 10 minutes Evaporation, or vaporisation, is a change of state from liquid to gas. The reverse process, condensation, is a change of state from gas to liquid. Talk to students about condensation that occurs on windows, or even in the bathroom. Dew is also a good example and offers the chance to talk about humidity in the air and what it means. It is also good to relate evaporation and condensation back to the processes that occur in the water cycle. The particle animations show evaporation on the left and condensation on the right. The liquid to gas (or gas to liquid) phase change occurs at the boiling point, which is the temperature at which the vapour pressure of the liquid equals the pressure of the environment surrounding the liquid. Due to this, boiling points are highly pressure-dependent. This can be related to the boiling point of water at altitude or to how a pressure cooker works. Answers: gas, liquid (Inquiry point 5) Evaporation (on left), condensation (on right) (Inquiry point 6) Increases (Inquiry point 7) Classroom demonstration: Place a small beaker of warm, but not hot, water into a bell jar attached to a vacuum pump after first recording its temperature. Evacuate the flask and watch the water boil. Ask students to predict the temperature of the water then check it. Talking point: Discuss the statement, 'Boiling is a cooling process.' (This just means that the most energetic particles are leaving the surface of the liquid, so the average kinetic energy of the particles remaining is lower. You can relate this to sweating as a means to cooling the body down, since the vaporising sweat carries energy away from the body.) SUBLIMATION 5 minutes In sublimation, a substance goes straight from solid to gas. Any substance can sublimate if the conditions of temperature and pressure are altered appropriately. Even water sublimes at extremely low pressures. Show a phase change diagram to identify the point at which sublimation could occur. Answer: Reducing the temperature could slow the rate of sublimation. (Inquiry point 8) Class demonstration: Show sublimation using dry ice or iodine. Talking point: Use the Science Extra on melting and boiling points to discuss why pressure affects one but not the other. Think about how pressure could affect sublimation. For example, dry ice sublimes easily at atmospheric pressure, but what if the pressure was greatly increased? Could it still happen? REVIEW 5 minutes Students complete a drag and drop exercise featuring particle views and answer a question. Answers (top to bottom): Melting, freezing, evaporation, condensation (Inquiry point 9) Sublimation (Inquiry point 10)

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CHANGING STATES (2) 5 minutes On this page, students label the state of four different elements under standard conditions. Answers (top to bottom): solid, gas, liquid, solid (Inquiry point 11) COMPLETE A DIAGRAM 5 minutes Students complete the review exercises to consolidate their knowledge. Answers: (Clockwise from top left) Condensation; Freezing/solidification; melting; evaporation/vaporisation (Inquiry point 12) After labeling the videos correctly, students complete their change of state diagram by dragging the components to the correct position. (Inquiry point 13) Suggested completion levels Basic - Inquiry point goal = 5 Students at this level will: recognise the terms melting, freezing, evaporation, condensation, sublimation. Core - Inquiry point goal = 8 Students at this level will: define the terms melting, freezing, evaporation, condensation, sublimation; understand what is meant by the term 'change of state'; identify the change in energy and arrangement of the particles during a change of state. Advanced - Inquiry point goal = 13 Students at this level will: define the terms melting, freezing, evaporation, condensation, sublimation; understand what is meant by the term 'change of state'; describe the change in energy and arrangement of the particles during a change of state; explain the difference between 'melting point' and 'boiling point', and contrast their pressure dependence.

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LESSON GUIDE

DIFFUSION IN THE LAB

Students explore the concept of diffusion by watching videos of experiments involving diffusion in liquids and gases. Diffusion is defined as the movement of particles from an area of high concentration to an area of low concentration. Suggested time: 45 minutes Summary of Key Learning Points Students: - learn the definition of diffusion - observe the permanganate experiment as an example of diffusion in liquids - discover that mass affects the rate of diffusion by watching the lead iodide experiment - watch a gas diffusion experiment involving precipitation to compare the rate of diffusion of gases compared to liquids - explore examples of diffusion in the home DIFFUSION IN THE LAB 5 minutes Read the definition of diffusion with students and ask them to relate that to the spray can of deodorant. What happens when the deodorant leaves the can? How long does it take to smell the deodorant? This should give students an idea how quickly diffusion occurs in gases. Answer: Yes (Inquiry point 1) Classroom demonstration: Spray a short burst of deodorant or perfume in one corner of the classroom with the door closed. Ask students to raise their hands as soon as they smell it. Talking point: Ask students how many everyday examples of diffusion they can think of. What sort of diffusion might happen in the body? PERMANGANATE EXPERIMENT 10 minutes The potassium permanganate is a common experiment used in schools to demonstrate diffusion in liquids. The video features the experiment, where a crystal of purple potassium permanganate is placed in each of three beakers. The beakers have different temperature water. Get students to visualise the water molecules in each beaker and imagine how quickly they are moving. This will help them predict which will diffuse more quickly. Tell them to imagine the purple permanganate ions breaking off from the crystal and being pushed through the beaker by the random movement of the water molecules. It may help to show an animation of Brownian motion. Answers: The permanganate ions will diffuse more quickly in the beaker with the hottest water because the water molecules are moving faster in that beaker compared to the molecules in the beakers with cooler water. The hotter the temperature, the faster the rate of diffusion (Inquiry point 2). LEAD IODIDE EXPERIMENT 10 minutes The rate of diffusion also depends on the mass of the diffusing particles. This is demonstrated by the lead(II) iodide precipitation. In order for the yellow colour to form, lead(II) ions (Mr = 207.2) on one side of the petri dish must meet iodide ions (Mr = 126.9) diffusing from the other side. The heavier lead ions move more slowly and so the precipitate forms closer to the side where the crystal of lead(II) nitrate was dropped. Note that the lead(II) nitrate is also less soluble than potassium iodide.

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Answer: Mass of diffusing particles also affects rate of diffusion. (Inquiry point 3) Talking point: Why are some substances, like vinegar, so much smellier than others, like oil? What has to happen in order for your body to detect an odour? Do you think the molecules in BO (body odour) are small or big? Why? AMMONIUM CHLORIDE EXPERIMENT 10 minutes This experiment involves ammonia (Mr = 17.034) and hydrogen chloride (Mr = 36.458). It occurs faster than the previous experiments because diffusion occurs more quickly in gases than liquids. Ammonia is a pyramidal molecule while hydrogen chloride is linear. It would be helpful to point out to students why this experiment should only ever be done by a teacher in a fume cupboard. The precipitate forms closer to the HCl because it diffuses less quickly than the lighter NH3. Answer: Nearer to acid. (Inquiry point 4) DIFFUSION IN THE HOME 10 minutes Drag drop answers (in order): faster, more, molecules, slower. (Inquiry point 5) The fundamental idea of diffusion is that it is not so much about the bulk movement of matter as it is about one substance spreading through another. For that reason, the choices from the home that would fit that idea are the burning toast (smoke particles spread through the air) and crying from chopping onions (sulfur compounds diffusing to the eye). The heater warming the room creates a convection current, but convection is not the same as diffusion. Water boiling to steam isn't a great example either. Yes, some water moves into the air, but it already contains water so there isn't a significant change in concentration at any point. Answers: Smelling burning toast from across the room, crying from chopping onions. (Inquiry point 6) Suggested completion levels Basic - Inquiry point goal = 2 Students at this level will: identify that diffusion involves the spreading out of particles. Core - Inquiry point goal = 4 Students at this level will: recognise that diffusion is the movement of particles from an area of high concentration to an area of low concentration; understand that changing temperature changes the rate of diffusion. Advanced - Inquiry point goal = 6 Students at this level will: describe diffusion as the movement of particles from an area of high concentration to an area of low concentration; explain that changing temperature changes the rate of diffusion; account for the fact that mass affects diffusion rate.

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LESSON GUIDE

EXPANSION EXPERIMENTS

Students make predictions about the effect of heat on various materials and watch videos of common expansion experiments. The 'particle view' in the videos gives students a chance to visualise what is happening at the particle level as heat is added. Suggested time: 45 minutes Summary of Key Learning Points Students: - learn that expansion involves an increase in volume - observe that solids expand only slightly with heat - discover that liquid expansion occurs more easily than solid expansion - find out that gas expansion is noticeable and rapid with the addition of heat - realise that cooling would produce effects opposite to those of heating EXPANSION EXPERIMENTS 5 minutes Discuss the idea of heating at a particle level with the students. Explain why expansion occurs when particles have more energy and talk about why the amount of expansion (for the same energy input) might be different in the three objects indicated: spoon, cordial, balloon. Answer: Balloon (Inquiry point 1) Class activity: Get a group of students to huddle close, moving slightly, to represent particles in a solid. Get them to move more and more as energy is added. They will have to move further apart to accommodate the extra movement. This is a model of expansion! Extension: Talk about pressure in relation to the balloon expanding. If heat is added, pressure inside the balloon increases. Since it has expandable walls, the volume will increase until the pressure inside the balloon is equal to atmospheric pressure. Talking point: What happens to density as expansion occurs? Remind students that density = mass/volume. The mass doesn't change, but volume increases. Hence, density decreases. EXPERIMENT 1: SOLID EXPANSION 10 minutes Students watch the first part of the video, which shows that the ball doesn't fit through the ring when they are both at the same temperature. Example answer: If the ring is heated the ball will fit through. On the next page, students watch the second part of the video. This shows the ring being heated. Now the ball fits through. Example answer: As heat is added to the ring, the particles vibrate faster while still staying in their fixed positions. They push each other slightly further away and the ring expands. (Inquiry point 2) Answer: Yes (the result would have been different since if the ball expands, it is even less likely to fit through the ring). (Inquiry point 3) The students can then watch the video with particle the view to show that heat causes increased vibration. Aim: To investigate the effect of heating the ring of a brass ball and ring. Conclusion: Heating the ring causes it to expand. (Inquiry point 4) EXPERIMENT 2: LIQUID EXPANSION 10 minutes Before students watch the video, they are asked to predict the effect of heat on the liquid in the thin glass tube. The answer is not as obvious as it may seem! Answer: Level of liquid dips then rises (Inquiry point 5) STATES OF MATTER © 3P Learning

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Students can watch the video first without particle view and then with particle view. They should note how the particles rapidly gain energy and move faster. Talking point: The energy required to change the kinetic energy of the particles depends on a substance's specific heat capacity. Water has one of the highest specific heat capacities (4.184Jg-1K-1) of any substance, so it takes a lot of energy to significantly change its temperature. How is this important to life on Earth? Example answer: As heat is added the glass expands, so the volume of the flask increases. This causes the liquid level to drop. Then, as the liquid itself heats and expands (due to the increased movement of the particles) the liquid level rises. (Inquiry point 6) Classroom demonstration: Heat equal masses of 3 different liquids (water, paraffin oil, ethanol) over Bunsen burners at the same time and measure which changes temperature fastest. EXPERIMENT 3: GAS EXPANSION 10 minutes Before students watch the video, it might be helpful to first discuss the Explore this on pressure. Once students understand that concept, they will have an easier time visualising why the balloon expands with heat. Answer: Pressure increases (Inquiry point 7) Complete sentence answers (in order): Expands, upwards, high, energy, more. (Inquiry point 8) Classroom demonstration: Put a small, air-filled balloon in a bell jar with a vacuum pump attached. Take the air out and observe what happens to the volume of the balloon. EXPANSION EXPERIMENTS (2) 10 minutes This activity has been all about heating and expansion, but what happens if the materials were cooled rather than heated? Get students to make predictions and then discuss their answers either in groups or as a whole class. Ask them to explain their predictions in terms of the Particle Model of Matter. Example answers: (Inquiry point 9) The ball would not have fitted through the ring if the ring were cooled (because the ring would have contracted). The liquid level should have risen slightly then sunk (because the glass would have contracted first and pushed the liquid up, then the liquid contracts and the level drops). The liquid level in the tube would have dipped (because pressure in the flask would have decreased). Suggested completion levels Basic - Inquiry point goal = 4 Students at this level will: understand that heating causes expansion; recognise that expansion is more obvious in gases compared to solids and liquids; relate expansion to the energy of the particles. Core - Inquiry point goal = 7 Students at this level will: explain why heating causes expansion; recognise that expansion is more obvious in gases compared to solids and liquids; describe expansion in terms of the energy of the particles; make predictions about, and draw conclusions from, expansion experiments; relate gas expansion to pressure. Advanced - Inquiry point goal = 9 Students at this level will: explain why heating causes expansion; recognise that expansion is more obvious in gases compared to solids and liquids; describe expansion in terms of the energy of the particles; make predictions about, and draw conclusions from, expansion experiments; describe pressure in terms of frequency and energy of collisions with the container walls; understand that gas expansion continues until internal pressure = external pressure.

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Complete the crossword using the clues given.

Across 3. When metals are heated they __________. 7. Heating causes particles to move __________ apart. 8. Heat energy is also known as __________ energy. 10. Pressure arises from ___________ of the particles with the walls of the container. 11. Adding heat increases the __________ energy of the particles. 14. When a substance is cooled, the particles lose ___________. 15. ____________ expand more noticeably than liquids. Down 1. In a solid, particles __________ in fixed positions. 2. The main thing you find out from an experiment is known as the _________. 4. All matter is made of __________. 5. Heating a sealed container of gas increases the __________. 6. The purpose of an experiment is known as the __________. 7. Particles move ___________ when heated. 9. If a balloon is put in the freezer it will ____________. 12. Contraction occurs when substances are __________. 13. In the ball and ring experiment, this is the part that is heated. __________ STATES OF MATTER © 3P Learning

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ANSWER SHEET

Complete the crossword using the clues given.

Across expand 3. When metals are heated they __________. further 7. Heating causes particles to move __________ apart. thermal energy. 8. Heat energy is also known as __________ collisions 10. Pressure arises from ___________ of the particles with the walls of the container. kinetic 11. Adding heat increases the __________ energy of the particles. energy 14. When a substance is cooled, the particles lose ___________. Gases 15. ____________ expand more noticeably than liquids. Down vibrate 1. In a solid, particles __________ in fixed positions. conclusion 2. The main thing you find out from an experiment is known as the ___________. particles 4. All matter is made of __________. pressure 5. Heating a sealed container of gas increases the __________. aim 6. The purpose of an experiment is known as the __________. faster 7. Particles move ___________ when heated. shrink 9. If a balloon is put in the freezer it will ____________. cooled 12. Contraction occurs when substances are __________. ring 13. In the ball and ring experiment, this is the part that is heated. __________ STATES OF MATTER © 3P Learning

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LESSON GUIDE

THE PARTICLE MODEL EXAMINER

Within the context of newspaper reports about problems caused by a heatwave, students investigate expansion and contraction phenomena in everyday life. They are required to explain these using the Particle Model of Matter. Suggested time: 45 minutes Summary of Key Learning Points Students: - discuss how a heatwave can cause infrastructure problems - learn why train tracks can buckle in the heat - observe that heat causes power lines to sag - investigate why sidewalks might crack in the heat - explore a method used to stop pipes warping - complete puzzles to summarise expansion concepts HEATWAVE BRINGS CITY TO STANDSTILL 5 minutes The activity starts on the front page of the newspaper. There is an article about a recent heatwave in the city that directly followed a month of cold weather. Discuss what happens when substances are heated and cooled. Define the terms 'expansion' and 'contraction' and get students to explain these using the particle model. Classroom demonstration: Get two old test tubes that you don't mind breaking. Rest one in ice water then take it out and put it straight into a hot Bunsen burner flame. Try the opposite scenario: strongly heat a test tube then plunge it into ice water. Why does glass break when suddenly heated or cooled, but not when heated and cooled over time? Use the particle theory to explain this to the students. RAIL MYSTERY BAFFLES 10 minutes The picture shows buckled train tracks. Get students to discuss the answers to the questions with each other before writing them down. Example answers: The hot weather causes the metal atoms to vibrate faster. They move further apart and the track expands. This causes buckling. Gaps could be left between lengths of track to allow room for expansion. (Inquiry point 1) After students have a go at writing a solution, the suggested solution comes up. The expansion joint shown is used in many structures, not just rail tracks. For example, all large bridges need expansion joints. Talking point: What might the expansion joint on a bridge look like? Ask students to have a go at designing one for a particular bridge. POWER LINES SAGGING 10 minutes This report greatly exaggerates the extent of sagging. In reality, power lines would not sag to the ground in the heat although they would hang more loosely than in cold weather. Answer: Wires snap (Inquiry point 2) Example answer: As the metal atoms in the wires gain heat energy, they vibrate faster. This causes them to move slightly further apart and the wires expand, resulting in sagging. (Inquiry point 3) Extension: Get students to look at the advertisements on each page. Can they work out the joke behind each one? If so, they are very clever!

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LESSON GUIDE

PAVEMENT CRISIS 10 minutes Cracked pavements are all over the place, but how can they be designed to never crack? Get students to discuss the events that have to take place for a pavement to crack and how it can be avoided. Example answers: As the particles in the concrete gain energy they vibrate faster and move further apart. This causes the concrete to expand. If there is not enough room for it to expand, it will crack. Instead of being made of large concrete blocks, the pavements could be made of smaller bricks with sand in between to allow for expansion. (Inquiry point 4) After students enter their answers, a suggested solution comes up. OVERHEATED PIPES FLOOD STREETS 5 minutes Obviously these days we would hope that people make pipes out of materials that wouldn't warp! This report supposes that metal pipes are used and they react badly to heat. The animation shows metal pipes getting hot and warping, and then shows a possible solution in the form of jointed pipes. Example answer: As the hot liquid runs through the pipes, the metal atoms absorb heat energy. They vibrate faster and the pipes expand. This can cause warping. Adding joints means that the joins can flex as needed when expansion occurs, which stops the pipes from warping. (Inquiry point 5) THE PUZZLE PAGE 5 minutes The end page is like the puzzle page of a newspaper. Students complete the exercises to bring up a joke about particles. Drag drop answers (in order): hot, vibrate, move, expand, gaps, buckle, dangerous, train, derail (Inquiry point 6) Word jumble answers: Expands (Inquiry point 7) Contracts (Inquiry point 8) Buckle (Inquiry point 9) Energy (Inquiry point 10) Random activity: What other words can you make out of the jumbled words? Answer: Spandex or greeny, but there are no alternatives for contracts and buckle! Suggested completion levels Basic - Inquiry point goal = 4 Students at this level will: define 'expansion' and 'contraction' in simple terms; identify one everyday problem associated with expansion and/or contraction. Core - Inquiry point goal = 7 Students at this level will: define 'expansion' and 'contraction'; describe why cooling causes contraction and heating causes expansion in terms of particle theory; identify and explain two everyday problems associated with expansion and/or contraction. Advanced - Inquiry point goal = 10 Students at this level will: define 'expansion' and 'contraction'; describe why cooling causes contraction and heating causes expansion in terms of particle theory; identify and explain at least three everyday problems associated with expansion and/or contraction; explain how density changes with expansion and contraction; draw the change in particle arrangement during expansion and contraction. STATES OF MATTER © 3P Learning

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THE PARTICLE MODEL EXAMINER

WORKSHEET Question 1

Complete the sentences using the following words. Each word is only used once.

cold, pavements, hot, contraction, crack, expand (a) ______________ weather causes metal rain lines to ______________ and buckling may result. (b) Power lines are hung loosely to prevent them snapping in ______________ weather due to ______________. (c) Heat can cause ______________ to expand and ______________. Question 2 Explain the following in terms of the particle model of matter. (a) The Eiffel Tower is shorter in winter.

(b) A steel fuel tank filled to the top with petrol will overflow if left in the Sun.

(c) Bread dough contains carbon dioxide generated by yeasts. When the bread is cooked, it rises.

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ANSWER SHEET

Question 1 Complete the sentences using the following words. Each word is only used once.

cold, pavements, hot, contraction, crack, expand Hot expand (a) ______________ weather causes metal rain lines to ______________ and buckling may result. cold (b) Power lines are hung loosely to prevent them snapping in ______________ weather due contraction to______________. pavements crack (c) Heat can cause ______________ to expand and ______________. Question 2 Explain the following in terms of the particle model of matter. (a) The Eiffel Tower is shorter in winter. The metal the Eiffel Tower is made of contracts in cold weather causing it to shrink. (b) A steel fuel tank filled to the top with petrol will overflow if left in the Sun. The liquid petrol will expand when heated causing it to overflow. (c) Bread dough contains carbon dioxide generated by yeasts. When the bread is cooked, it rises. The carbon dioxide gas bubbles expand when heated causing the bread to rise.

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LESSON GUIDE

USING MODELS IN SCIENCE

Students learn about the definition of a scientific model and sort through some examples to find out what does and does not constitute a model. They then look more closely at the advantages and disadvantages of the Particle Model of Matter. Suggested time: 30 minutes Summary of Key Learning Points Students: - learn that pool balls can model gas molecules - explore the nature of a scientific model - discover that the size of models is usually scaled up or scaled down - understand that some things can be explained using the particle model and some things cannot - acknowledges that there are advantages and disadvantages to the Particle Model of Matter USING MODELS IN SCIENCE 20 minutes A well-known scientific model is the billiard ball model of gas molecules. This is obviously a simplified analogy for gas molecule interactions. It ignores intermolecular forces and views collisions as perfectly elastic. For this activity, the billiard ball model should only be discussed on a very simple level. Let students watch the balls moving around the table, then ask them to compare that to air (nitrogen and oxygen) molecules moving around the classroom. Example answers: The balls are like gas molecules because they have mass. The balls are not like gas molecules because they are coloured. (Inquiry point 1) Talking point: Discuss some of the different types of models. For example, the billiard balls are an analogical model. There are also others such as mathematical models, instructional models and iconic models. Ask students to offer their own definition of a model and compare it to the one given in the activity. Look around the classroom. What examples of scientific models are present? What distinguishes a scientific model from another kind of model? When students feel comfortable with the answers to these questions they can proceed with the activity. Answer: The scientific models are Earth, molecule, solar system, torso, cell, DNA. (Inquiry point 2) Once students have selected the scientific models and left the other objects (puppy, fashion model and book) behind, they are asked to label the models as scaled up, scaled down or actual size. Discuss what these terms mean and give them examples. Answers: Earth - scaled down Molecule (ethane) - scaled up Solar system - scaled down Torso - actual size (approximately) Cell - scaled up DNA - scaled up (Inquiry point 3)

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LESSON GUIDE

THE PARTICLE MODEL OF MATTER 5 minutes Students look at the six different pictures to determine what can and cannot be explained using the particle model. Refresh students' memories about what the Particle Model of Matter is and what its basic tenets are. Answers: Eiffel Tower - Does explain (Inquiry point 4) Colour of beanie - Does not explain (Inquiry point 5) Balloon weight more dense than balloon - Does explain (Inquiry point 6) Ice floats on water - Does not explain (Inquiry point 7) Diatomic molecule - Does not explain (Inquiry point 8) Deep-sea fish - Does explain (Inquiry point 9) USING MODELS IN SCIENCE (2) 5 minutes Talk to students about the fact that all models have their advantages and disadvantages. For example, look at an architect's model of a house they have designed. What can and what can't it show? Although most models don't show the finer detail, they are still useful in helping to visualise and understand concepts. Example answers: Another advantage is that the model explains changes in pressure when a gas is heated or cooled. Another disadvantage is that the model doesn't explain why heating the same mass of different substances results in a different temperature change. (Inquiry point 10) Talking point: Why does ice float on water? Is water the only solid that expands on freezing and why does it do that? What percentage of an iceberg is underwater and how does that relate to the density difference between solid and liquid water? Suggested completion levels Basic - Inquiry point goal = 4 Students at this level will: recognise that a model is usually a simplification of a concept; identify one example of a scientific model; state one benefit and one limitation of the particle model. Core - Inquiry point goal = 7 Students at this level will: recognise that a model is usually a simplification of a concept; identify at least two different types of scientific models; state at least two benefits and limitations of the particle model; understand why models are used in science. Advanced - Inquiry point goal = 10 Students at this level will: recognise that a model is usually a simplification of a concept; explain how models are used in science with examples of at least three different types; state at least three benefits and limitations of the particle model.

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chemical sciences - 3P Learning

IntoScience TEACHER RESOURCES & INFORMATION GUIDE TEACHING THE AUSTRALIAN CURRICULUM WITH INTOSCIENCE: CHEMICAL SCIENCES - YEARS 7 & 8 IntoScience ...

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