20046 AC Science Year 6 Chemical sciences

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Australian Curriculum Science (Year 6) 

Published by R.I.C. Publications ® 2011 

Copyright @ R.I.C. Publications ® 2011 

Revised 2017 

RIC-20046 

Titles in this series: 

Australian Curriculum Science (Foundation) 








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For all Australian Curriculum material except elaborations: This is 

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This material is reproduced with the permission of ACARA. 

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Foreword 

Australian Curriculum Science - Foundation to Year 7 is a series of books written specifically to support the national curriculum. Science 

l i teracy texts introduce concepts and are supported by practical hands-on activities, predominantly experiments. 

All Science Understanding and Science as a Human Endeavour substrands for each level are included. Science Inquiry Skills and overarching ideas 

underpin all topics. 

Titles in this series are: Australian Curriculum Science - Foundation 

Australian Curriculum Science - Year 1 







Contents 

Teachers notes ................................................................... iv-vi How are earthquakes and tsunamis related? .................... .42-44 

Scope and sequence ................................................................ vii How submarine earthquakes can create tsunamis .................. 45 

Scientific method ................................................................... viii How are earthquakes measured?.. .................................... 46-48 

Investigation format ................................................................ ix Earthquake research .............................................................. 49 

Biological sciences ......................................................... 2-17 

How important is soil? .......................................................... 2-4 

Best conditions for growth ....................................................... 5 

What are fungi and what do they do? .................................... 6--8 

How are volcanic er u ptions monitored? ........................... 50--52 

Ring of Fire eruptions ............................................................ 53 

What are the effects of dro ught? ....................................... 54-56 

Clean water for all! ................................................................. 57 

Foul fungi ................................................................................. 9 Ph y sical sciences .......................................................... 58-81 

n Why do plats and animals need to adapt? ....................... 10-12 How does electricity flow? ................................................ 58-60 

Plant and animal adaptations ................................................. 13 Connecting circuits ................................................................ 61 

Why do animals migrate or hibernate? ............................. 14-16 

What are electrical conductors and insulators? ................ 62--64 

Migration and hibernation ..................................................... 17 Conductor or insulator? ......................................................... 65 

Chemical sciences ........................................................ 18-37 

What happens when materials are mixed? ........................ 18-20 

Clean dirty water .................................................................... 21 

What is solubility? ............................................................. 22-24 

The effect of particle size and stirring on solubility ................. 25 

What changes do heating and cooling cause? ................... 26-28 

Just add salt! .......................................................................... 29 

Why do metals rust? ......................................................... 30-32 

Rusting nails .......................................................................... 33 

How is reversible change used in recycling? ..................... 34-36 

Recycling paper ..................................................................... 37 

Earth and space sciences .............................................. 38-57 

How do light globes work? ............................................... 66--68 



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What causes a volcanic eruption? ..................................... 38-40 

Create the most explosive volcano .......................................... 41 

Electromagnetism unplugged! ................................................ 69 

How do wind and water generate electricity? .................... 70--72 

Making the most of water power ............................................ 73 

How do we get power from the sun? ................................. 74-76 

Solar-powered pathways ......................................................... 77 

Which energy sources for the future? ............................... 78-80 

Sustainable energy sources on tap .......................................... 81 

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CURRICULUM SCIENCE (Year 6)

Teachers notes 

Each book is divided into four sections corresponding to the four substrands of the Science Understanding strand of the curriculum. Shaded tabs 

down the side of each book provide a quick and easy means to locate biological sciences, chemical sciences, Earth and space sciences or physical 

sciences substrands. 

Science as a Human Endeavour units or questions, as set out in the Australian Curriculum, are included in all substrands. 

Science Inquiry Skills are included in all units. The skills utilised are listed on each teachers page. 

The six overarching ideas (Patterns, order and organisation; Form and function; Stability and change; Scale and measurement; Matter and energy; 

and Systems) underpin each science literacy text page and are included as much as possible throughout the comprehension pages. 

Each substrand is divided into a number of four-page units, each covering a particular aspect and following a consistent format. 

The four-page format of each unit consists of: 

• a teachers page 

• student page 1, which is a science literacy text about the concept with relevant diagrams or artwork 

• student page 2, which includes comprehension questions about the literacy text 

• student page 3, which involves a hands-on activity such as an experiment. 

FOUR-PAGE FORMAT 

Teachers page 

The first page in each four-page format is a teachers page which provides the following infor m ation: 

• A shaded tab gives the 

Science Understanding 

substrand. 

• The title of the four-page 

un i t is given. 

• The content focus (the 

particular aspect of the unit 

covered in that set of four 

pages) is given. 

• The inquiry skills focus 

covered within the four pages 

is set out. 

What are fungi and what do they do? 

Coaut(Otld; Tbebeuiourofl'uogi..tlbdrroleln 

foodproduaionaod:spoibge 

I.Teacher clteck;answerscwld iRdude:theycanbegood orbad, 

big or small. Theycu klll ormre.Theycan destroy food or be 

lmporlllntinprodudngfood.'ff,eyareabltllkeplantsand abitlke 

anlmalsyettheyare nelther. 

2.{1)Theydecomposedeaclorgmic:1!12!1er.Theyfeedasparasiles on 

lrang.llesh. 

{b)eJIZ}ID8 

3.(a)fromtheoul:!ide.ib 

(b)fromtb.einsidewi: 

4. (a)Inrespirat,onlyarboodlol:idelsproduced .In +---+ 

fermenl2iloD,tkohol lsalsoproduud 

(b)ResptratioooccunitotKpresence olatr.FermenW:lonoccurs 

witbllttlcocoou 

5.( a)cubondloxkleproducecwrtngmplratioo 

(b )alooholpnxb:eddurin&fermentatioo 

6. {a)Enzymesproducedbytbemouldbreakdownthebeans illlo a 

, ... 

.. 

{b)F.nzymesprodl1Cl'dbytbe)edbre3klhepmedowntoaliquid 

and produce de5irab!iblwn;. 

Teacherrheclr. 

,,.. 

Studc ntswilldisr.ofctha1flllglgrowlnall condltionscxccptlnfreezing 

temperature;. the gt'('1iC gr°"1h oooirs where conditions arc warm 

mdd,mp. 

• Answers and explanations are 

provided where appropriate 

for student pages 2 and 3 (the 

comprehension questions 

relating to the text and the final 

activity in the set of four pages). 



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• Preparation states any 

material or resources the 

teacher may need to collect to 

implement a lesson, or carry 

out an experiment or activity. 

• Background information, ---+---- 

--------+-- • The lessons provides 

information relating to 

implementing the lessons on 

the following student pages. 

which includes additional 

IF'i!''ui:!· "!!:!:I" ir1!· ·CHI::!!' CEi:':l:!7':!ll-ili:, ·:l:i&·1•+11v:nnm&:c&+ill¥N•-:-.J••••11 fl!+:!· 1111111 moam -- m-ii 

information for teacher and 

student use and useful websites 

relating to the topic of the 

section, expands on the unt. 

AUSTRALIAN CURRICULUM SCIENCE (Year 6) 

- 

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. 


FOUR-PAGE FORMAT (continued) 

Student page 1 

The second page in the four-page format is a science literacy text which introduces the topic. This page provides the following infonnation: 

• A shaded tab down the side gives the Science 

Understanding substrand. 

• The title of the unit is given. This is in the fonn of 

a question to incorporate science inquiry skills and 

overarching ideas. 

• The science literacy text is provided. 

• Relevant diagrams or artwork enhance the text, 

or are used to assist student understanding of the 

concepts. 


hat are fungi and what do they do? - I 

Fungi ore s!ronge organisms. They ore ooilher 

planl nor ooimol but ar11 similar to bath. They 

eonbe110tir,y !hot omicroecopeleneededk> 

see !hem or'° lorge thlJI 1hcy oon be seen 

:: !t:i;=:o:;;,Joo 

Olh&rs,likeciflafhcopandcfestroyingcmgei.. 

eonldllyou.Some fl.mgicon curuinfeclion$ 

(rrom perricillium comes the penicillin 

= 

I.'. 

Mouds ood yeosts are types of fungi. They 

oon deslroy food. Mould will grow on any 

moislfooditem lhotisl11nlong11nough 

In worm conditions. But some yooel!I and 

=: e b: 1 i::::, 

oon oolonthesugarin canncd sondfinks 

ondtcrmoorbondiwdde. 

5om9 c11e1111118 are mould rip&ned. The 

: :! :e::i;t i:t!::d a == 

"-"'"'· ,·· fl) Oheflo=bocomes.Brie o,odc.-, 

eJCisl in al Y!lrieties of environment: in air, 80i l The longer 

Unli11f"enplante,f1Jngi do nolneed 

sunligh1 10 grow.They obtointheirfoodfrom 

dead orgonic molter or they ve as parasites 

on lvlngflesh.Fungl ore lmportant ln olfood 

webs. AB they feed, they produce subskmces 

ai led 6flZ}'11SSWhich break dow n the orgonic 

mctter,releosing energybockinlolhesoil 

in lheformotnutrients.Fungi grawbe!ltin 

domp,wam,oondltlons. 

lhe cheese Is left, the stronger 

ore coated with a ne layer ofwhire mould 

oodlheflavourdevelops fromthe outside in. 

Thisis coll8dsurfaca ripening.SHtonand 

OanlshblueorelnJectedwllhbluemouldond 

lhaflavourd11velop5fromtheinside. 

Wlhout yeost,breadoould nolrlseoncl 

fruitand cel'80Igroin could natfem,ent lo 

produc:ewineandbeer. 

Yeost woos in two ways. Wnh oir, the yeast 

mnvertssugar ta oorbon diaxide.This 

prooeooisoolledrespilTJtion.Wnhttreorno 

air,sugorisoonverted to olcohot ondcarbon 

diaxide.This processis called'9tm6ntation. 

lnbreoclmaklng, balh processeoccur. 

Carbon dioxid11 from r11Spiration causes 1111 

doughtorie.eondfermentafionpmduche 

deliciov$smcll.The olcohol lholitproduced 

indot>ghis dHtroyed durlngboking. 

In me production of soy aouoe, 1"$1 o mould 

is oddcd 10 breok down the soy beons in100 

pasle.Ayeostthenfeedsonthepaste ond 

ln dolng soproduoes anquldwllhdeslroble 

llowura.Anar obout arnanth,lhe liquidill 

1eodytobe separatad,sterilisedtakilllhe 

yoosts ondmoutds,ondbollledreodyfor 

llllleossoy souce. 

1 1· ,I f-c.i IE 

The second student page consists of a series of questions or activities relating to the literacy text. They aim to gauge student understanding of the 

concepts presented in the text. Many of these questions relate to overarching ideas relevant to that age level as stated in the Australian Curriculum 

Science. 

IWhat are rungl and what da they da? - 2 

u .. 1111 tut on 7 IO eompi.te the following. 

I. In your own woros, explain why funi;rl are st range organtsm, 

-· 

2. (a} Fungi obtainltoodtromlwol!OUl'Ces.What are they? _______ 

(b} Fungioon eo,rg0nic m0tterbeoousethey produe9sub&l0nces rhotbre0k lt 

Wh

. 

. 


FOUR-PAGE FORMAT (continued) 


The third student page provides a hands-on activ i ty. It may be an experiment, art or craft activity, research activity or similar. 

• A shaded tab gives the Science Understanding 

subst r and. 

• The title is given. This will be different from the 

previous two pages, but will be a related to the 

concept focus of the unit. 

• An adapted procedure for an experiment, craft 

activity or a research activity is given. 

Science as a Human Endeavour units and questions 

I 

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Physical sciences 

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Earth and space 

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Chemical sciences 

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Biological 

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The growth and survival of living things "' e1 

o. 

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g. 

1 are affected by physical conditions of their 

environment 

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(ACSSU094) 

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Changes to materials can be r e versible or 

irreversible (ACSSU095) 

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Sudden geological changes and extreme 

weather events can affect Earth's surface 

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(ACSSU096) 

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Electrical energy can be transferred and 

tr a nsformed in electrical circuits and can 

be generated from a range of 

sources (ACSSU097) tl!"/!!i 

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Science involves testing predictions 

by gathering data and using evidence 

to develop explanations of events and 

phenomena and reflects historical and 

cultur a l contributions (ACSHE098) 

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Scientific knolwedge is used to solve 

problems and inform personal and 

community decisions (ACSHElOO) 

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With guidance, pose clarifying questions 1:'; '2 

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investigations 

(ACS!S232) 

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Identify, plan and apply the elements of 

scientific investigations to answer questions 

' I ' I and solve problems using equipment and 

materials safely and identifying potential 

risks (ACS!S103) 

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Decide variables to be changed and 

measured in fair tests, and observe measure 

' ' I and recrod data with accuracy usng digital 

technologies as appropriate 


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Construct and use a range of 

representations, including tables and 

, I graphs, to represent and describe 

observations, patterns or relationships 

in data using digital technologies as 

appropriate (ACSIS107) 

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Compare data with predictions and use 

' I as evidence in developing explanations 


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Reflect on and suggest improvements to 

scientific investigations (ACS!S108) 

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Communicate ideas, explanations and 

,1,1,1,1,1,1,1,1,1,1,1,1, ,1,1,1, ' , I processes using scientific representations 

in a variety of ways, including multi-modal 

texts (ACSISllO) 

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Scientific method 

Subject 

Question 

Background research 

Hypothesise 

Test hypothesis 

Analyse data 



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Communicate results 


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R.I.C. Publications ®

_____ l_n_v_e_s_tigation format 

Title 

(What am I investigating?) 

Prediction 

(What do I expect to discover?) 

Procedure 

(How am I going to 

set up the investigation?) 

Equipment 

(What do I need? 

How do I use it?) 

Reliability 

(How will I ensure a fair test?) 

Observations/Measurements 

(How will I record what I 

see and/or measure?) 

Analysis of results 

(What do my results show? 

How do they relate to my prediction?) 

Developing explanations 

(What do my results mean?) 

Communicating 

(How will I present my results?) 



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Reflecting on methods 

(How effective was my method 

for this investigation? 

How would I change the method to 

provide more meaningful data?) 


m 

AUSTRALIAN 


What happens when materials are mixed? 

Content focus: Possible outcomes when materials are 

mixed 

Inquiry skills: Planning and conducting 

Processing and analysing data and 

information 

Evaluating 

Communicating 

Background information 

• Most reversible changes are physical changes. 

• Materials can be changed by mixing with another material, heating, 

cooling and burning. 

• Reversible changes made by mixing materia l s can be reversed by 

filtration ( of insoluble materials), evaporation ( of soluble materials), 

sieving (materials of different sizes) and pouring (liquids of different 

densities). 

• Some actions create an irreversible physical change; for example, 

beating an egg alters the consistency of the egg irreversibly but the 

chemical composition of the egg is the same. 

• Useful websites: 

- 

- 

- 

- 

Preparation 

• The students will need some knowledge of the following terms: 

- evaporation: the process of converting a substance into a 

gaseous state or vapour 

- filtration: the process of passing a liquid through a filter (a 

device made from cloth, paper, porous porcelain, or a layer of 

charcoal or sand) to recover solids 

- miscible: capable of being mixed 

- immiscible: incapable of being mixed 

- particle: a minute portion, piece or amount 

- solvent: the substance in which a solute dissolves 

- solute: the substance t h at dissolves in a solvent 

- solution: the mixture of a solvent and a solute 

- soluble: describes a solid that will dissolve 

- insoluble: a solid that will not dissolve 

- solubility: the degree by which a solute will dissolve in a given 

volume of the solvent at a given temperature 

- siphon: to transfer using a siphon (an enclosed tube or similar 

through which a liquid is conveyed from a container at one 

elevation to a lower elevation). The liquid is forced into the tube 

by suction or immersion and then, once the tube is raised with 

a short section to the higher end and a long section to the lower 

end, the liquid falls (due to gravity), creating suction at the higher 

end which draws liquid through the tube. 

• For the activ i ty on page 21, the students should use colanders and 

sieves of different sizes and types; for example: absorbent paper and 

coffee filters, a range of plastic and acrylic containers and funnels. 

The lessons 

• After the students have read page 19, explain the concepts and 

ensure they understand all the terms included. (See Preparation.) 

• For the test on page 21, dirty the water using a range of nonhazardous 

materials. For the test to be fair, each group must be given 

an equal volume of the test water after it has been stirred thoroughly. 

Compare filtered samples by collecting in clear acrylic glasses and 

observing them against a plain wh i te backing. This will highlight any 

debris remaining in the water. 

Answers 

Page20 

1. Across: 1. soluble 4. reversible 9. distillation 

10. miscible 11. separation 

Down: 1. sieving 2. filtration 3. reaction 

5. evaporation 6. density 7. particles 

8. siphoning 

2. Step 1: Filter the talcum powder from the water. 

Step 2: Evaporate the water from the solution to leave the salt 

crystals. 

3. In a reversible change, there is no chemical reaction between the 

materials and no new substance is formed. The materials can return 

to their original state. In an irreversible reaction, a new substance is 

formed, which is evidence that a chemical reaction has taken place. 

The materials can not return to their original state. 

4. Sand and sugar can be separated because the particles of sugar 

dissolve in water, which can be filtered to remove sand and soluble 

sugar can be retrieved by evaporation. 



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Page21 

Students should investigate websites such as 

and view images such as before commencing their design. The students should consider the 

methods of separating liquid-solid mixes such as those on page 19. 


m 



What happens when materials are mixed? - I 

When different materials are mixed together a number of things may happen. 

Liquid-liquid mix 

Example I : The liquids do not 

mix. They are immiscible. The 

more dense liquid sinks to the 

bottom and the less dense 

rises to the top. 

They do not react with each 

other. The two liquids can be 

separated by siphoning. 

Examples: 

olive oil and water 

Example 2: The liquids do 

mix because they have equal 

density. They are miscible. 

They do not react with each 

other. This is a reversible 

change.They can be 

separated by distillation. 

The liquids are heated until 

the lower boiling point of the 

two liquids is reached. This 

vapour is then collected in a 

condenser, where it returns to 

its liquid phase. 

Examples: 

water and fruit 

juice 

Example 3: The liquids do 

mix because they have equal 

density. They are miscible. 

Liquid-solid mix 

Example I: The solid does 

not dissolve. It is insoluble in 

the liquid. 

There is no chemical reaction 

between the two. The solid 

can be separated by filtration. 

Examples: 

vinegar and 

sawdust 

Example 2: The solid 

dissolves. It is soluble in the 

liquid. 

There is a chemical reaction 

between the two, resulting 

in a new substance being 

formed. The change is 

irreversible. The solid can not 

be separated from the liquid. 

Examples: 

vinegar and baking soda 

W 

BAKING 

. 

:

What happens when materials are mixed? - 2 

Use the text on page 19 to complete the following. 

I • Write the words to complete the puzzle. 

Across 

I . Solids that dissolve in a liquid are 

this. 

4. A change that can be returned 

back to its original state. 

9. A way of separating two liquids. 

I 0. Liquids that mix together are this. 

I I . Splitting up. 1. 

7. 

II. 

9. 

2. 

6. 

4. 

10. 

5. 

Down 

I . A way of separating two solids of 

different sized particles. 

2. A way of separating a solid from a liquid 

in which it is insoluble. 

3. This can occur between two substances. 

5. A way of separating 

a solid from a 

3. 

liquid in which it is 

soluble. 

6. The mass of a 

substance in a 

8. given volume. 

7. Small pieces of a 

solid. 

8. A way of separating 

two immiscible 

liquids. 

2. Explain the steps to separate a mixture of table salt and talcum powder. 



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3. What is the difference between a reversible and an irreversible change? 

lf. Explain why sand and sugar can be separated. 


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Clean dirty water 

Clean water is essential for everyone, yet for many people in the world their 

water supply is contaminated and needs to be purified in order to be safe to 

use. 

In groups, your task is to use a selection of simple kitchen equipment and 'tf,/ 0 ---- 

household materials to design the best filtration system for cleaning dirty water. 1 •: 

How will you ensure a fair 

challenge for each filtration 

system? 

How will you compare the 

filtered samples? Is this a 

fair comparison? 

Draw and label a sketch 

of your design, explaining 

how it works. 

Did water pass easily 

through the system? 

What parts of the design 

worked well? 

Before you begin 

Designing your system 

Evaluate your design 



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What parts of the design 

need improving? 

What feature contributed 

to the most successful 

design? 

Evaluating all designs 

What feature contributed 

to the least successful 

design? 


m 

AUSTRALIAN 


Content focus: Features of solubility 

Inquiry skills: Questioning and predicting 

Planning and conducting 


information 

Communicating 


• The solubility of a solute is the maximum amount that can be 

dissolved in a given volume of solvent at a given temperature. 

• In terms of liquids and solids, when a solvent (liquid) dissolves 

a solute (solid), the particles of the solvent separate the particles 

of the solute and then fill the spaces between. The molecules of 

some solutes and solvents are polar, meaning they have positive 

and negative electical charges. This allows attraction between the 

molecules and greater solubility. 


- 

- 

- 

Preparation 

• Make an illustrated chart defining the words associated with 

solubility. Include familiar examples of solutes such as sugar and 

salt, and solvents such as water and oil. 

• For the experiment on page 2 5, students will need sugar cubes, acrylic 

tumblers, marker pens for labelling, water at room temperature, 

measuring jugs, knives, stirrers and stopwatches. 

The lessons 

• The words associated with solubility are very similar and can 

be confusing. Discuss the meaning of each so that students are 

clear about which is which. Give examples, or find clues, to assist 

understanding and recall of definitions. 

• For the experiment on page 25, discuss how the test will be fair. The 

amount of solute must be the same for all tests so any stray sugar 

must be added to the tumbler it belongs with. Measuring the water 

must be done accuratel y. It is better to use a narrow jug than a wide 

one. The same person should stir the three stirred samples to ensure 

consistency of force. Discuss the point at which the solute is seen to 

be completely dissolved: one moment it can still be seen, the next 

moment it can't. 

What is solubility? 

Answers 

Page24 

1. (a) The solvent separates the solute particles and distributes them 

evenly throughout the water. The solvent dissolves the solute 

particles from the surface layer inwards, until all particles have 

been dissolved. 

(b) Increasing the surface area of the solute by crushing it into 

smaller particles; stirring the solute as it is added to the solvent 

2. (a) The mixture of a solute and a solvent 

(b) The solid that is dissolved by the solvent 

(c) The substance that dissolves the solute 

( d) The greatest amount of solute that can be dissolved in a known 

quantity of solvent at a given temperature 

( e) The point at which no more solute can be dissolved 

(0 A solution containing the maximum amount of solute 

3. (a) high solubility 

(b) low solubility 

4. by raising the temperature of the solution 

5. (a) The solution would no longer look clear. 

(b) The solute would not dissolve and could be seen as the solution 

becomes very cloudy and solute could be seen at the bottom of 

the glass. 

6. Because it can dissolve so many different solutes 

Page25 

Students will discover that the solute in Tl takes longest to dissolve and 

that in T6 dissolves in the least time. The greater the surface area, the 

faster the dissolving time. If stirring is also incorporated, the time is 

reduced. 



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What is solubility? - I 

When a substance dissolves in water, the powder or crystals are broken down into even 

smaller particles and distributed evenly throughout the water. This mixture of a solid 

dissolved in a liquid is called a solution. The solid is called the solute and the liquid is the 

solvent. The solvent separates the solute particles and takes up the space between the 

solute particles. 

{water) 

solvent 

particles 

{sugar) 

solute 

particles 

solution 

{water) 

solvent 

particles 

{sugar) 

solute 

particles 

saturated solution 

The maximum amount of solute that can dissolve in a known quantity of solvent at a certain 

temperature is its solubility. Some things (for example, salt) are highly soluble in water 

because they dissolve easily. A solute that does not dissolve easily (for example, pepper) 

has low solubility. 

A solute can be made to dissolve faster. 

When a solute dissolves, it does so only on the outer surface of each particle. As the 

outside layer is dissolved, it exposes the next layer. This continues until the whole particle 

has disappeared. So a solute in a form with greater surface area will dissolve faster than 

those with lesser surface area; for example, a sugar cube dissolves more slowly than the 

same weight of sugar as loose crystals. 

When a solute is stirred into a solvent, the stirring action brings the solute particles into 

contact with more solvent, thereby also increasing the dissolving rate. 

A liquid solvent can only dissolve a given amount of solute at a given temperature. If any 

more solute is added, the solution will no longer look clear. It will start to turn cloudy and 

the solute can be seen at the bottom of the container. When the solution stops looking 

clear, the solvent has reached its saturation point for that solute at that temperature 

and is called a saturated solution. There is no room in the solvent for any more solute 

molecules. But if the solution is heated, more solute can be dissolved until the saturation 

point for the solvent at the higher temperature is reached. 

Not all solutes dissolve in all liquid solvents. Water is known as the 'universal solvent' 

because there are many solutes that will dissolve in it. 

Solubility is an important factor in the manufacture of dehydrated foods. Instructions on the 

packets of dehydrated foods tell you how much water, stock or milk is required to make the 

product to the correct consistency. Such foods have made a significant contribution to the 

welfare of people living in areas where fresh foods are not readily available; for example, 

dried milk, which has all the nutrition of fresh milk, has been a life saver for young children 

living in famine struck areas of the world and where there have been natural disasters. 

R.I.C. Publications" www.ricpublications.com.au 

m 



Display Copy 

AUSTRALIAN 


What is solubility? - 2 


I. (a) What happens to the solute as it is added to a solvent and dissolves? 

(b) Write two ways a solute can be made to dissolve faster. 

2. Write the definition for each word or phrase. 

(a) solution 

(b) solute 

(c) solvent 

( d) solubility 

(e) saturation point 

(f) saturated solution __________________________ 

3. Match the correct pairs 

(a) dissolves easily • 

(b) 

does not dissolve easily • 

• low solubility 

• high solubility 



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4. How can a saturated solution be made to dissolve more solute? 

5. (a) How could you tell that a solution was reaching its saturation point? 

(b) 

What would happen if more solute is added to a solution after the saturation point is 

reached? 

6. Why is water called the 'universal solvent'? 


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The effect of particle size and stirring on solubility 

How long does it take for a solute to dissolve in a solvent? 

The answer to this question depends on the surface area of the solute particles and how much, 

if any, stirring takes place. 

You will conduct an experiment to determine how particle size and stirring affect the time it 

takes for sugar to dissolve in water that is at room temperature. 

Prediction: 

What do you think will be the outcome of this experiment? 

[ ] 

You will need: 

• 24 cubes of sugar • 6 acrylic tumblers labelled from TI to T6 • stirrer 

• water at room temperature • measuring jug • knife • stopwatch 

What to do: 

0 Prepare the solute. Q Add the solute to the solvent. 

• Leave 8 sugar cubes for TI and 

T2, whole (4 for each). 

• Cut the sugar cubes for T3 and 

T4 in half (8 halves for each). 

• Cut the sugar cubes for TS and 

T6 into quarters ( 16 quarters for 

each). 

f) Add 200 ml of water to all tumblers. 

Results: 

Record all times in the table. 

(a) 

(b) 

Time for solute to dissolve 

Add the 4 whole sugar cubes to TI and 

at the same time, start the stopwatch. 

Record the time it takes for all the sugar to 

dissolve. 

Add the 4 whole sugar cubes to T2 and at 

the same time, start the stopwatch. Stir 

the solute for 5 seconds after adding 

the cubes. Record the time it takes for all 

the sugar to dissolve. 

Repeat steps (a) and (b) for T3 and T4, and 

then for TS and T6. 



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Whole cubes Halved cubes Quartered cubes 

Without stirring With stirring Without stirring With stirring Without stirring With stirring 

Tl T2 T3 T4 TS T6 

Conclusion: 

What can you conclude from this experiment? 

[_____] 


m 

AUSTRALIAN 


What changes do heating and cooling cause? 

Content focus: How temperature changes affect the 

molecular structure and bonding of a 

substance and how this alters the state 

of the substance 




information 

Evaluating 


• Heating and cooling can cause changes to substances, some 

reversible, some irreversible. 

• Almost all substances have freezing, melting and boiling points. If 

a substance is not a mixture or not contaminated in any way, these 

temperatures can be used to identify or confirm the identity of a pure 

substance. 

• Heating and cooling a substance changes its state from solid to liquid 

to gas (and vice versa if the change is reversible). This is related to 

how tightly the molecules of the substance are held together. 


- 

- 

- 

- 

Preparation 

• For the activity on page 29, provide water, table salt, spoons, 

weighing scales, containers, measuring jugs and stirrers for making 

up the solutions. Also provide thermometers capable of measuring 

low temperatures and access to a domestic freezer. 

The lessons 

• Take time to explain the concept of the bonding of atoms within 

molecules, and bonding in the solid, liquid and gas phases. This 

can be done in an open space w i th each child playing the part of 

a molecule. In a solid, the molecules are held together in a rigid 

structure. Group the students into rows and columns. They place 

the left hand on the shoulder of the person in front of them and put 

the right arm around the person to their right. Their arms are the 

bonds holding the molecules together. In the column to the right and 

the row at the front, each molecule has an unused bond, this is for 

attaching to more molecules. In a liquid, the bonds are still present 

but as it is heated, the molecules start to move and loosen the bonds. 

To show this, students jog on the spot and loosen their right arm 

bonds. In doing so they move further apart. They are starting to melt! 

In a gas, the bonds are broken completely and the molecules are 

free to take up the whole space available to them. Students drop both 

arms and move around the whole area. Only if they are contained in 

a small area can they be cooled and condensed. 

• For the investigation on page 29, students should make up about six 

salt water solutions of known concentration; for example: 2.5%, 5%, 

7.5%, 10%, 20% and 50%. As a control, they will need a plain water 

sample. All weighing must be carried out on the same scales and 

water measured using the same apparatus. When the solutions are 

made, they will be placed in a domestic freezer and examined at set 

intervals of time for ice formation. At this point, the temperature of 

the sample is taken. Students should initially record their results in 

a table and then graphically showing, salt concentration vs freezing 

temperature. Students may need to be reminded what a control and 

a fair test are (refer to pages 2 and 6). 

Answers 

Page28 

1. (a) false (b) true (c) false (d) true 

2. (a) boiling point (b) molecules 

3. (a) liquid (b) gas (c) solid 

4. (a) When a liquid is heated above boiling point 

(b) When a gas is cooled below boiling point. 

5. The heat energy is used to break the bonds holding the liquid 

molecules together and instead forms a gas. 

6. They must be collected and cooled. 

Science as a Human Endeavour questions 

Nature and development of science 

Teacher check 

Students can research the freezing, melting and boiling points of 

substances such as water, milk, sunflower oil etc. 



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Page29 

Teacher check. Students should find that the more salt is added, the 

lower the freezing point. 


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What changes do heating and cooling cause? - I 

Atoms are the building blocks of everything. 

Most things are made up of two or more 

types of atom. They are joined together 

as molecules by forces of attraction called 

bonds. A well-known example of a molecule 

is water, which is made of two atoms of 

hydrogen bonded with one atom of oxygen. 

A water molecule 

When a substance is heated and cooled, 

it changes between the states of solid, 

liquid and gas. In a solid, the molecules, 

held together as a rigid structure. As the 

substance is warmed, the molecules begin 

to move and separate from each other as 

the bonds among them weaken. This is what 

happens as a solid melts. The more heat that 

is applied, the faster the molecules move. 

When a substance is cooled, the reverse 

happens. The molecules slow down and 

move closer together, until they form their 

rigid structure again. 

MP 

 

e, 

'Ii- L' ., 

\),ri/!, 

IC\Ulu 5tart5 to 

evaporate. 

t 

Solid i5 completely 

melted. 

Time 

When a solid substance is heated, the 

temperature at which it starts to melt is called 

its melting point. This is the same temperature 

at which the substance in its liquid form starts 

to freeze when it is cooled. The melting and 

freezing points of a substance are the same. 

As a solid substance continues to melt, its 

temperature does not rise even though it is 

still being heated. The heat energy is being 

used to speed up the molecules of the solid 

until the substance is all liquid (at which point 

its temperature will start to increase). That 

is why snow, even as it is melting, is always 

cold. 

When a liquid substance is heated, the 

temperature at which it starts to boil is 

called its boiling point. The bonds between 

the molecules are broken and the liquid 

evaporates as the molecules disperse as a 

gas. 

The gas can be collected in a condenser and 

cooled to a liquid again. If it is not collected, 

the gas spreads into the atmosphere. 



Display Copy 

6P 

t 

LiC\uid i5 completely 

evaporated. 

MP- Melting point 

6P - 6oiling point 

The water cycle is an example of the constant change of state of a substance. Water is 

constantly moving among its three states of matter. In oceans, lakes, swimming pools and 

puddles, water evaporates into water vapour (gas), which later condenses and falls as rain, hail 

or snow. When the temperature falls to O °C and below, ice forms. 


m 

AUSTRALIAN 


Use the text on page 27 to answer the questions. 

I. Answer as true or false. 

(a) 

(b) 

The molecules in a solid move very quickly. 

When a liquid is cooled, its molecules slow down. 

(c) 

(d) 

The molecules of a gas are tightly held together. 

The freezing and melting temperatures of a substance are the same. 

2. Read the clues to find the answers to the riddles. 

(a) 

(b) 

I am a reading on a thermometer. When I am reached, the molecules of a substance 

move very fast and break apart from each other as the bonds among them are broken. 

The substance begins to evaporate. What am I? 

I am a b __________ P---------- 

We are groups of atoms held together by attractive forces. In a solid, we are stationary 

and held as a rigid structure. In a liquid, we can move a little and are held together 

more loosely. In a gas, we are completely free unless we are captured in a condenser 

and cooled down. What are we? 

We are m _________ _ 

3. In which state or phase (solid, liquid or gas) is a substance in if its temperature is: 

(a) 

(b) 

(c) 

between melting point and boiling point? 

above boiling point? 

below freezing point? 

4. (a) When does evaporation occur? 

(b) 

When does condensation occur? 



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5. When a liquid is heated to its boiling point and continues to be heated, the liquid does not 

get any hotter. Why not? 

) 

6. For condensation to occur, what must happen to the escaping gas molecules? 

The freezing, melting and boiling points of various substances can help scientists identify unknown 

substances. Find out these values for a number of familiar substances. Plot them on a graph to 

compare them. 


m 



Just add salt! 

In places that experience cold winters, when icy roads create hazardous driving conditions, 

some local councils spread salt on the roads to reduce the freezing point of 

the water on the roads' surface. This reduces the temperature at which it 

turns to ice. This can reduce the freezing point of the water to far below O °C. 

Your task is to find out how much the freezing point of water is reduced 

when known amounts of salt are added to the liquid. 

Complete the table by answering the questions. 

How many salt water test 

solutions will you make? 

How much salt will you 

add to each salt water 

solution? 

What will you use as the 

control? 

How will you ensure a fair 

test? 

What do you expect 

the outcome of the 

investigation to be? 

How will you carry out the 

test? 

What equipment will you 

need? 

How will you record your 

results? 



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How will you present your 

results? 

How did your results 

compare to your 

prediction? 

What changes would you 

make to improve your 

investigation? 


m 

After your investigation 

AUSTRALIAN 


Content focus: Conditions and chemical reactions that 

cause rusting 




information 

Communicating 


• When iron corrodes, rust is formed and the iron loses its metallic 

properties; i.e. electrical conductivity, strength and shine. The 

process, which occurs through oxidation ( combination with 

oxygen), produces iron oxide (rust). 

• Rusting is an example of corrosion, which is an electrochemical 

process in which electrons given up by the iron combine with oxygen 

in the presence of water and accumulate as rust. 

• Steel is used commonly in the construction of buildings and other 

large structures, as well as household items. It is an alloy of iron, and 

is iron with carbon added to increase strength. It also increases iron's 

ability to resist oxidation, and does not rust as easily as wrought iron. 

• Non-reactive metals, such as gold, are resistant to oxidation. They 

are called noble metals. They occur naturally although they are rare. 

• Reactive metals such as iron are mined in their ore states. A metal 

ore, found in rock, contains traces of the metal. The ore is extracted 

by mining and then refined to obtain the metal. 

• Dynamite, which is used extensively in the mining, quarrying and 

construction industries, was invented by Alfred Noble. 


- 

- 

Preparation 

• Make a collection (or find pictures) of rusting objects for students 

to view and discuss. 

• For page 33, provide sufficient nails, plastic cups, salt, stirrers, 

measuring jugs and weighing scales for each student or group of 

students. 

The lessons 

• After examining the rusting object, note how corrosion eats at the 

metal. Discuss the implications of this for safety and longevity of 

metal objects. Discuss what students already know about protecting 

metals from corrosion. 

Why do metals rust? 

• For the activ i ty on page 33, the students need to accurately prepare 

a number of salt solutions of different concentrations, add a nail ( or 

similar metal object) to each solution and observe what happens 

over time. They need to draw up a table to record their observations 

for each solution sample. To ensure a fair test, all metal objects 

should come from the same source and be free of rust. They must 

be non-galvanised. The water must come from the same tap and be 

of the same temperature. The salt must come from the same packet. 

Students record what they expect to see and then exactly what they 

do see. Discuss their observations, allowing them to derive an 

explanation. 

Answers 

Page32 

1. rust 

2. (a) air and water 

(b) Teacher check Students should include the components: metal, 

air, water and rust 

3. When salt water evaporates from metal, it leaves salt behind. The 

presence of salt speeds up the rusting process. 

4. (a) Acid dissolves metal. 

(b) Acid dissolves rust before it attacks metal. 

5. (a) A metal that combines easily with other elements/react more 

readily/corrode easil y. 

(b) the more reactive metal 

6. Humid; there is a lot of moisture in the air, which continues the 

rusting process. 

Science as a Human Endeavour question 

Nature and development of science 

.::. 

Teacher check 

- • 

Visit the website to find a 

list of Nobel Prize winners. 

Page33 

• Students will need to make up a number of salt solutions of increasing 

and known concentration. 

• They will also require a plain water control. 

• For a fair test, the metal they use must be the same for each solution; 

e.g. iron nails from the same packet. 

• At set times, they will have to record exactly what they see happening 

in each solution. These observations are best recorded in a table. 

• Students will observe that rusting occurs more rapidly in the strongest 

salt solution. The chemical reaction that takes place on the surface 

of the metal involves electron transfer which occurs more rapidly in 

salt water because salt water is a better conductor of electricity than 

plain water. 



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Why do metals rust? - I 

I 

metal+ air+ water= rust 

If a steel bicycle is left out in the rain, orange-red marks will 

soon appear on the chain, sprockets, handlebars and other 

places where the metal is unpainted. This is rust. If nothing is 

done to stop it, the rust will continue to corrode the metal. 

Rusting is an irreversible change. Oxygen in the air and rain 

water have combined with the metal and created another 

substance, which is known as iron oxide. 

Water is the main cause of rusting. When it comes into contact 

with an unprotected metal, two reactions begin. Hydrogen in 

the water combines with carbon dioxide in the atmosphere and 

forms a weak acid. As the acid begins to dissolve the metal, oxygen in the water combines with 

the dissolving metal and iron oxide (rust) is formed. This corrosion cycle will continue for as long 

as the metal is in contact with water or even if the air is heavy with moisture, like it is on a hot 

and humid day. 

Scientists have discovered that some metals react with water and oxygen more readily than 

others. Reactive metals corrode easily. Through scientific discovery, a list ordering metals 

from the least reactive to the most reactive has been produced. This list has been valuable for 

scientific progress. 

How to prevent rusting 

• Keep the metal dry or dry it thoroughly after it has been wet; e.g. keep your bicycle in the 

shed and always wipe it down if you have been cycling in the rain. 

• Cover the metal with oil or grease, which repel water; e.g. always oil your bike chain 

after you have cleaned it. 

• Paint the metal; e.g. the garden gate, outdoor metal furniture. 

• Use metal that has been galvanised-an industrial method for coating metals with 

a protective layer of a less corrosive metal; e.g. used in car manufacturing and ship 

building. 

• Use sacrificial protection; e.g. placing layers or blocks of more reactive metals next to or 

on ship hulls, oil rigs and underwater pipelines. The block or coating of metal rusts rather 

than the metal it is protecting. However, the sacrificial metal must be replaced before it is 

completely corroded. 

During the rusting process, at the same time as the acid is 

dissolving the metal it also dissolves the existing rust. Because of 

this, stronger acids are often used to clean rust because they will 

dissolve the rust before they attack the metal. 

In some places, rust can be a significant problem because the 

presence of some chemicals in the environment adds to the 

rusting process; for example, where saltwater spray from the 

ocean reaches cars and buildings, or where acid rain is a problem. The salt and other chemicals 

which are dissolved in the water remain on the metal after the water evaporates, and can speed 

up the rusting process. 


m 



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AUSTRALIAN 


Why do metals rust? - 2 


I • Iron oxide is the chemical name for which common problem? _______ 

2. (a) What two elements are required for the rusting process to occur? 

_______________ and _______________ 

(b) 

Draw a flow chart to explain how rust is formed. 

3. Rain causes metal to rust, but sea spray causes it to rust more quickly. 

Explain why this is so. 

4. Explain how acid can: 

(a) 

damage metal 

5. (a) What is a reactive metal? 

(b) 

(b) 

clean rusty metal 



Display Copy 

If pieces of two different metals were left together in a tray of water, which would rust 

first? Tick the correct answer. 

the more reactive metal D the less reactive metal D 

6. Rusting would be a greater problem in a _______ (dry/humid) climate because 

Alfred Nobel was a famous scientist who discovered dynamite. For over I 00 years, the Nobel Prize has 

been awarded each year to recognise scientific advances. Research some Nobel Prize winners and 

their contribution to scientific discovery. 


m 



Rusting nails 

Does a stronger salt solution mean that rusting will occur more quickly? 

Devise an investigation to answer the question. 

What equipment 

will you need? 

What will you do? 

How will you 

ensure a fair test? 

How will you record 

your data? 

What I think will 

happen. 

What did happen? 

Resu Its/Observations 



Display Copy 

Explain what 

happened. 

How would you 

compare the rate at 

which the different 

metals corroded? 

Conclusion 

Further investigation 


m 

AUSTRALIAN 


How is reversible change used in recycling? 

Content focus: The reversible changes that allow 

recycling of glass, pla s tic and paper 

products 

Inquiry skills: Communicating 

Background infonnation 

• There is no limit to how often glass can be recycled, provided it is not 

contaminated. To prevent contamination with other materials, only 

cleaned clear, green and brown bottles and jars should be recycled. 

• Glass is made from sand, silica and limestone. In the manufacture 

of most glass products, recycled glass, cullet, is added to these raw 

ingredients. The cullet lowers the overall melting point of the mixture 

and so less energy is required in the manufacturing process. 

• Downstream recycling means that the recycled product (for 

example, plastic or paper) is of reduced quality compared to the 

original product from which it came. This means that, unlike glass, 

these materials can only be recycled a limited number of times. 


- 

- 

- 

Preparation 

• Obtain/Draw large colourful flow charts of the recycling processes of 

glass, plastic and paper. 

The lessons 

• Collect examples of glass, plastic and paper waste. Discuss their 

differences and how they would be sorted at a recycling plant. 

Discuss the reversible change element of the recycling process of 

each material. 

Answers 

Page36 

1. To reduce the amount of rubbish going into landfill; to conserve 

natural resources that are used to make new materials. 

2. Recycling processes rely on the reversible change from solid to 

liquid and back to solid; the chemical properties of the materials 

allow them to be heated and cooled and yet remain unchanged. 

3. Glass: waste glass collected; sorted into different colours; crushed 

into cullet; sand, limestone and soda ash added; heated to melting 

point; moulded into new bottles. Plastic: waste pla s tic collected; 

sorted into different grades; shredded into flakes; heated to melting 

point; formed into nurdles; sold in bulk. 

4. Recycled glass is used to make the same products it came from; e.g. 

glass bottles. Recycled plastic is not used to make the same products 

it came from but is formed into nurdles and used in the manufacture 

of other products. Recycled glass requires the add i tion of other 

materials to the cullet. 

5. To identify the grade of plastic used to make the item and for accurate 

sorting at the recycling centre. 

6. Glass and pla s tic are heated to their melting points to become 

molten. Water is added to paper to return it to pulp. The paper pulp 

is deaned a number of times. 

Science as a Human Endeavour question 

Use and influence of sciences 

Teacher check 

Page37 

1. (a) To reduce the impact on the environment caused by industrial 

paper making; for example: felling trees, and air and water 

pollution. Recycling paper uses less energy and also reduces 

landfill. 

(b) Most paper in everyday use-including newspapers, 

magazines, junk mail pamphlets, telephone directories, office 

waste and cardboard-can be recycled. 

(c) Pulping: Adding water and beating to separate fibres. 

Screening: To remove contaminants greater in size than pulp 

fibres. 

Centrifugal cleaning: Contaminants that are more dense than 

pulp fibres are thrown to the outside and separated as the pulp 

slurry is spun at high speed. 

Flotation: Ink particles are attracted to chemicals added to the 

slurry. As air is passed through slurry, the chemicals foam and 

rise to the surface. 

Kneading/Dispersion: Contaminants are reduced in size by 

beating. 

Washing: Small particles of contaminant are rinsed away from 

the pulp. 

Bleaching: Chemicals are added to brighten the paper if 

required. 

Papermaking: The recycled fibre is used to make paper by the 

same process as pulp from bark. 

Dissolved air flotation: The water used in the recycling process 

is cleaned and reused. 

Waste disposal: The sludge remaining is buried, burned or used 

as fertiliser. 



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How is reversible change used in recycling? - I 

We all know how important it is to recycle as much material 

as we can. This helps to reduce the volume of rubbish going 

into landfill sites and to conserve natural resources that are 

used to make new materials. 

Recycling glass and plastic is possible because the chemical 

properties of both materials allow them to be heated and 

cooled and yet remain unchanged. But unlike simply melting 

and refreezing an ice block, industrial recycling is more 

complicated. 

There are many different 

grades of recyclable plastic, all of which are used for different 

products. For example, high-density polyethylene (DHPE) 

is used for plastic jugs and some toys, and low-density 

polyethylene (LDPE) is used for food wrapping and plastic 

bags. Have you ever noticed the triangle formed with three 

arrows which is printed on plastic containers? It usually 

has a number between one and seven inside the triangle and letters outside it. This label 

identifies the type of plastic the item is made from and is used when plastics are sorted 

during the first stage of the recycling process. 

After it is separated into its different grades, the plastic is shredded into flakes. In this state, 

the material is heated to its melting point. The molten plastic is formed into pellets known as 

nurdles, which are sold in bulk and used in the manufacture of other products (for example, 

engineered woods like plywood and MDF). 

Recycling plastic does not reduce the need for manufacturing new plastic but it can reduce 

the demand for other resources; for example, less trees are felled to make wood products 

because engineered 'wood', which is stronger and more durable, is made using the plastic 

nurdles. 

With glass recycling, after it is collected the glass is sorted by colour (green, brown, clear 

etc.). After this the glass is crushed into small pieces and is then referred to as cullet. 

Before the cullet is melted in a furnace, other raw materials used to make glass are added. 

These include sand, limestone and soda ash. After being mixed at approximately 1500 °C, 

the glass can be moulded into new bottles and other products. 

Like glass, the paper making 

process is also reversible, allowing 

the tonnes of waste paper created 

every year to be used again. 

Water and chemicals are added 

to the waste paper, which is then 

reduced to slurry in a pulper. The 

pulp goes through a number of 

cleaning processes before being 

made into paper again. 



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m 

AUSTRALIAN 


How is reversible change used in recycling? - 2 


I. Give two reasons why recycling materials is important. 

Sit 

2. Why is it possible to recycle materials such as glass and plastics? 

3. Use the steps written below to create a chart for the recycling of glass and plastic. One step 

is used for both materials. 

crushed into cul/et 

formed into nurdles 

waste plastic collected moulded into new bottles 

sorted into different colours heated to melting point 

sand, limestone and soda ash added 

Glass 

sold in bulk 

shredded into flakes 

waste glass collected 

sorted into different grades 

Plastic 

Lf. What is the main difference between recycling glass and recycling plastic? 



Display Copy 

5. What is the purpose of the triangular label embossed on plastic items? 

6. How do the recycling processes for glass and plastic differ from the paper recycling 

process? 

Watch the animation at to view the recycling process from start to finish. 

Decide if each stage shows reversible or irreversible changes. 


m 



Recycling paper 

Recycling paper requires less energy than making new paper from bark. 

The process is very effective and takes only a few days to complete. 

The need for paper made from new pulp can be reduced by recycling 

all paper waste and buying paper products made from recycled paper. 

Research information to complete the table. 

(a) 

Why should people recycle paper? 

. 

 

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(b) 

(c) 

What types of paper can be recycled? 

Explain with a sentence the ten steps of the paper recycling process. 

Pulping 

Screening 

Centrifugal 

cleaning 

Flotation 

Kneading/ 

Dispersion 

Washing 

Bleaching 



Display Copy 

Papermaking 

Dissolved air 

flotation 

Waste 

disposal 


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AUSTRALIAN

20046 AC Science Year 6 Chemical sciences

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