Energy and Change [Grade 7 English]

WESTERN CAPE PRIMARY SCIENCE PROGRAMME

ENERGY AND CHANGEGRADE 7

We welcome the wide use of these materials. Please acknowledge the PSP. © PSP 2001

An example of a short learning programme in the Natural Sciences

Activity 1: Looking for different forms of energyActivity 2: Burning a candleActivity 3: Different fuelsActivity 4: Doing our own reading and research about oil and gasActivity 5: Comparing three different fuelsActivity 6: Transport and fuelActivity 7: Why do fuels cost money?Activity 8: What about fuels in the future?

Contents• This booklet illustrates an example of a short learning

programme for Grade 7.• It develops concepts, skills, attitudes and language in

a step-wise fashion.• It includes activities and tasks for learners, teacher tasks,

support materials and assessment suggestions.

Page . . . . . .Subject

2 . . . . . . . . .Activity 1 Looking for different forms of energy

4 . . . . . . . . .Activity 2 Burning a candle

7 . . . . . . . . .Activity 3 Different fuels

8 . . . . . . . . .Activity 4 Doing our own reading and research about oil and gas

12 . . . . . . . .Activity 5 Comparing three different fuels

17 . . . . . . . .Activity 6 Transport and fuel

21 . . . . . . . .Activity 7 Why do fuels cost money?

25 . . . . . . . .Newspaper business report

26 . . . . . . . .Activity 8 What about fuels in the future?

28 . . . . . . . .Suggested workscheme for this learning programme on energy . . . . . . . . . .and change

29 . . . . . . . .Sheet for assessing a task

30 . . . . . . . .Class recording sheet for task assessment

31 . . . . . . . .Blank assessment sheets

33 . . . . . . . .Codes for recording

APPENDIX

34 . . . . . . . .Task card: Activity 2: Burning a candle

35 . . . . . . . .Task card A : Activity 5: Comparing three different fuels

36 . . . . . . . .Task card B: Activity 5: Comparing three different fuels

37 . . . . . . . .Task card: Activity 6: Looking at different vehicles

38 . . . . . . . .Task card: Activity 7: Why do fuels cost money?

39 . . . . . . . .Fact sheets on ‘Oil and Gas in South Africa’

43 . . . . . . . .Xhosa translation: ‘Renewable and non-renewable energy sources’

44 . . . . . . . .Xhosa translation: ‘How much does crude oil cost?’

45 . . . . . . . .Labels of different types of energy

46 . . . . . . . .Five pictures on different forms of transport

Cover . . . . .‘Energy and Change’ mindmap

Course presented by Rose Thomas and Sandra Mahote

Booklet designed by Welma Odendaal and illustrated by Janet Ranson

and Nicci Cairns

Western Cape Primary Science Programme

Edith Stephens Wetland Park

Lansdowne Road

Philippi 7785

PO Box 529Howard Place7450

Tel: 021 691-9039 Fax: 021 691-6350

e-mail: [email protected]

website: www.psp.org.za

DEVELOPED BY WESTERN CAPE PSP TEAM AND TEACHERSThis learning programme will work towards the following learning outcomes in the Natural Sciences

s LO1: Scientific InvestigationsThe learner will be able to act confidently on curiosity about natural phenomena, and to investigate relationships and solve problems in scientific, technological and environmental contexts

s LO2: Constructing Science KnowledgeThe learner will know and be able to interpret and apply scientific, technological and environmental knowledge

s LO3: Science, Society and the EnvironmentThe learner will be able to demonstrate an understanding of the interrelationships betweenscience and technology, society and the environment.

2

Looking for different forms of energy

1. Hand out old newspapers, one to each group of learners. Thepictures and advertisements in the newspapers illustrate examples ofdifferent forms of energy. For example, motorcars, appliances andmachines of any kind all use and produce certain forms of energy.People and plants and animals all use and produce certain forms ofenergy.

2. Also hand out the small labels (electrical energy, heat energy, soundenergy, light energy). See Appendix page 45.

Placing energy labels on pictures in newspapers1. Look at the pictures in old newspapers and magazines and find all the

different forms of energy (heat energy, light energy, sound energy,movement energy and electrical energy).

2. Put labels on all the places where you found the different forms ofenergy.

3. Explain to your group why you have placed the label there and what the energy is doing at that place.

4. Write one sentence about each form of energy that you found and what it was doing e.g;

The radio needs electrical energy to play music.

• There are different types (forms) of energy – heat, light, sound, movement, electricity (Nuclear energy (atomic energy) and stored energy are also forms of energy but we will not deal with these here)

Activity 11

Key concepts

Learner task GROUP

NOTE …

While the learners are

placing the labels, check

to see that they are

correctly identifying the

forms of energy. You

can assess learners while

they are doing this.

Teacher task

3

Looking for different forms of energy

What we want to assess What we expect from learners

Placing energy labels on to Learners must:pictures k Correctly identify the different

forms of energy by placing labels in appropriate places on the pictures.

Writing sentences about the The sentences must say:different forms of energy k What form of energy it is

k Where the energy is doing something

k What the energy is doing.

ActivityAAsssseessssmmeenntt 11

what?

where?

4

Burning a candle

1. Write these key words on the board e.g. burn, stored energy (in thewax), wax, fuel, heat and light energy, wick, oxygen, and energy.

2. Hand out the candles to each group of learners, and use theappropriate key words to point out the parts of the candle.

3. Light the candles and write the following questions on the board.

• Energy can be changed from one form (kind of energy) to another• The process of burning also changes energy from one form to the

other• Fuels are substances that we burn in order to get heat and light

energy• Fuels contain stored energy

Activity 22

Key concepts

Teacher task

QQuueessttiioonnss• What does a candle need to burn?• What is happening when a candle burns? • Where did the candle get its energy from? • What energy do we get from a burning candle?

NNeeww wwoorrddss

Flame, smoke, melting, match, sound energy/ crackling

KKeeyy wwoorrddss

wax, fuel, heat and light energy, wick, oxygen, energy

4. Facilitate a class discussion for learners to explore their own ideasabout the answers to the questions. Write any new words on theboard so that learners can fill in the table below.

5. Ask learners to fill in the ‘I think.... ‘ column in the table below, givingtheir own ideas.

6. After that, ask learners to read the piece on ‘Energy from a burningCandle’ on page 6. Finally, they complete the‘I know.........’ column with the answers they find

from reading the piece.

5

1. Look at the burning candle, and discuss it with you group using thequestions to help you.Questionsk What does a candle need to burn?k What is happening when a candle burns? k Where did the candle get its energy from? k What energy do we get from a burning candle?

2. Fill in the ‘I think…’ column in the table below.3. Read the paragraph ‘Energy from a burning candle’ on page 6 to find

the answers to the questions.4. Now fill in the ‘ I know…’ column in the table below using the correct

information from the reading.

Burning a candle

Learner task GROUP

Questions I think … I know …

What does a candle need It needs a match to light it. A candle needs a match, a in order to burn? wick, wax and oxygen to burn.

What is happening when The wax melts and the candle There is an energy changea candle burns? gets smaller. when a candle burns.

Where did the candle get The candle got its energy from The candle got its energy fromits energy from? the match. the wax. The energy was

stored inside the wax.

What energy do we get We get light energy from a We get heat and light energy from a burning candle? burning candle. from a burning candle.

Sometimes we get some sound energy as well.

6

Energy from burning a candleYou have seen a candle burn. You have felt heat energy from the flame. Italso produces light energy.

k You must have heat from a match to light your candle. When you light the candle, first the wick begins to burn until a little ofthe wax has melted. Then the melted wax goes into the wick and alsocatches alight. Thereafter, both the wick and the wax burn.

k You also need oxygen from the air to keep the candle burning. A substance that burns with oxygen is called a fuel. So wax is the fuelof the candle.

k When a candle burns there is an energy change taking place. Wax is changed when it burns. Chemicals in the wax join with oxygenas the fuel burns. Heat energy and light energy are given off. Thestored energy inside the wax is changed to heat and light energy byburning the candle.

k People burn fuels because the fuels have stored energy. When we burn fuels we get heat and light energy. People use fuelsbecause we need heat and light energy.

k We also need fuels to make engines work. Inside a motorcar engine the petrol has to burn and give off heatenergy to make it work. Aeroplanes and ships also have engines inwhich fuel is burnt.

Burning a candle


Completing the ‘I know ‘ column The answers to the questions about ‘Energy from burning must match the informationa candle’. in the reading.


7

Different fuels

1. With learners, make a mind map on the chalkboard about differentfuels and their uses.

2. Once you have completed the mind map, focus the learners’ attentionon two main categories of fuels, i.e. oil and gas. Inform them that theyare going to RESEARCH some information on oil and gas by reading.Then they will present the information in the form of a poster.

• People use many different fuels e.g., wood, coal, oil, paraffin petrol etc.

Activity 33

Key concepts

Teacher task

NOTE …Remind learners thatfuels are sources ofenergy. In other words,we have to burn fuel toget energy. So electricityis not a fuel although it is a source of energy.

fires for heating, power

stations, factories

FFUUEELLSS AANNDDTTHHEEIIRR UUSSEESS

W00d

0il

gas

petr0l

diesel

paraffin

c0al

fire, cooking,

heatingmotor cars,trucks, motorbikes, taxis,tractors

taxis, boats,lorries, tractors,buses, trains

primus stoves, lamps, lightsstoves, lights, camping

plastics, ships,planes

8

Introduction 1. Ask learners to raise as many questions as

they can about oil and gas. Ask : “What do you want to know aboutoil and gas?” Then the learners must makeup questions about oil and gas beginningwith words like: what, where, why, how,when, what if, who?

2. Write their questions on the board in a mind map.3. Now write up the specific questions on page 9. Compare the

learners’ questions with the specific questions and show that many of the questions are the same.

• Crude oil and gas are important natural sources of energy• Crude oil and gas were formed over millions of years, in the

Earth’s crust, from tiny dead animals and plants• Mining companies drill deep into the Earth’s crust to find oil and

gas. The hole in the Earth’s crust through which the oil or gas comes to the surface is called a well.

• Oil and gas are transported from these wells to places all over the world

• Crude oil is used to make fuels and many other useful products

Activity 44

Key concepts

Teacher task

QQUUEESSTTIIOONNSS::OOIILL && GGAASS

How is oil and gas transported?

Why do ships carry oil?

What if we didn’thave oil and gas?

How much does it cost?

How are oil and gas made?

Who uses oil and gas?

Where do we get oil and gas?

What are oil and gas usedfor?

Doing our own reading and researchabout oil and gas

Specific questionsa. Why are oil and gas important?b. Where do oil and gas come from?c. What is crude oil?d. What things are made from oil and gas?e. How do oil and gas products get to the user (the customer)?f. How are oil and gas formed?g. How do we find oil and gas?h. How do we get oil and gas from under the ground?i. How are oil and gas transported?j. How is crude oil refined into a finished product?k. Where did the energy come from that is stored inside gas and oil?

4. Tell learners that you have information for them on the specificquestions. They will choose some questions and then research theinformation to find the answers.

Setting up groups to do their reading research1. Divide your class into groups of 5. Let each group choose two or

three questions to research.2. Read the information sheet ‘A guide to Oil and Gas in South Africa’

with your class on page 39–42.Note: Make sure learners can understand and explain any difficultwords or concepts. For example: Crude oil is the oil that is found naturally far under-ground in the Earth’s crust. After it has been brought to the surface, ithas to be changed or refined so that we can use it. The oil and petrolthat we buy for our motorcars have been refined from crude oil.

Setting the task for the learners1. Hand out the task cards to the learners and explain what they have to

do.2. Explain to the learners what you will expect on the poster:

k a suitable headingk good illustrationsk appropriate and correct informationk artistic layout and lettering (this means that you must

arrange everything on the poster in a clear and artistic way)

9

10

3. Let learners do the research (reading for information) in class. Beavailable to help them with vocabulary and other questions.

4. Set a time for the making of the poster as a group project. (for a weeklater) This is so that the learners have time to prepare their informationfor the poster.

5. On display day, each group puts together all its information onto itsown poster.

6. Check each poster to make sure that all the information is correct.Give time to each group to correct any errors.

7. Each group then presents its poster to the class orally. Assist learnersto speak clearly and loudly. Allow question time so that learners canask the whole group questions if anything needs to be clarified.

8. Display the posters in the class until you have finished the theme‘Energy and Change’.

In some parts of theworld, an oil rig isused to extract oiland gas from the

bottom of theocean.

11

Making a poster aboutoil and gas in SouthAfrica1. Read about Oil and Gas in South

Africa.2. Choose two questions to research3. Read to find the answers to the

questions. Write out any relevantinformation about those questions inyour own words. Your information mustbe correct.

4. You may also draw pictures to show whatyou have found out. The pictures musthave labels to explain them.

5. Next week you will have to put yourdrawings and writing on a poster, which will be made by the wholegroup.

6. The poster must have: k a headingk good illustrations with labels or explanatory notesk correct information about the questions you have researchedk everything must be artistically arranged on the poster

7. You must be able to explain your information and drawings on theposter to the rest of the class, and answer questions about them. (You must be able to explain in a clear, loud voice, and give the correct information.)

Doing our own reading and research about oiland gas

Learner task GROUP



Making a poster about oil and The poster must have:gas in South Africa k a suitable heading relating to the topic about

oil and gas

k correct information that answers the questions that the learners have chosen

k drawings or pictures that suitably illustrate something about what the learners have researched

k illustrations must have labels or captions to explain what they are about

k an artistic, neat presentation

12

1. Show learners three different fuels (candle wax, methylated spirits andparaffin).

2. Explain to learners that they will carry out an investigation to test andcompare three different fuels. They do this by seeing how quickly eachfuel can heat water to boiling point.

3 Ask the learners to predict which of the three fuels will boil water first.4. Hand out the task card and the apparatus (see learner task card) for

each group to carry out the investigation.k A candlek A spirit burner with methylated spiritsk A spirit burner with paraffink Glass baby food bottles or beakersk Waterk Syringes or measuring cylinders to measure out the waterk Tripod stands and gauze matsk Matches to light the candles and burners.

• Fuels store energy and we have to burn them to get the energy out

Activity 55

Key concepts

Teacher task

Comparing three different fuels

13

Comparing three different fuels1. Set up your apparatus like this:

2 Compare what happens when you use three different fuels to boilwater. Use these questions to help you to make your observations:k What colour is the flame? k Which fuel causes pollution? What kind of pollution does it give off?k Which fuel is the first to boil the water?

3. Write your observations in the table below:

What do I want to findout about the fuels?

What must I do tofind out?

What must I do totest the three fuels

in a fair way?

Which fuel will be thefirst to boil the

water?

Learner task

The flame is yellow.

The candle gives off a smallamount of smoke.

The bottom of the bottle getsdirty.

This fuel is the last to boil thewater.

The flame is blue.

It gives off a smell when it is burning.

This fuel is the first to boil thewater.

The flame is orange.

This gives off a lot of smokeand a bad smell.

The bottom and sides of thebottle become black.

This fuel is the second to boilthe water.

A candle Methylated spirits Paraffin

WaterWire gauze

Tripod stand

Candle

WaterWire gauze

Tripod stand

Spirit burner

Paraffin

Water

Tripod

SpiritburnerMethylatedspirits

14

1. Facilitate a discussion with the class about comparing the three fuels.Make sure the following points come out in the discussion:k Learners compare the fuels by using each fuel to boil water

(Remind learners that water boils when it bubbles vigorously)k To compare the three fuels fairly, learners must use the same

amount of water with each fuel k It is not necessary to have the same amount of fuel as long as there

is enough to bring the water to the boil k Learners also have to make sure that all the water starts off at

about the same temperature (they take it from the same jug or bottle)

k The fuel that takes the shortest time to boil the water, is usually methylated spirits

k Paraffin gives off a smell and a lot of black smoke. It also gives off black greasy soot that covers the outside of the bottle

2. On the chalkboard write any new words that are introduced by thediscussion and explain them: e.g. soot – the sticky black stuff that sticks to the bottom of the glassbottle, smoke, pollution, greasy, smelly gas, etc.

Teacher task

NOTE …

When we use paraffin in a

primus stove in our homes, we

have to pump air into it, to

make the primus work. The fuel

mixes with air and this helps it

to burn much more efficiently.

So it gives out a lot more

energy and it does not make so

much smoke and soot.

15

1. Write a report about comparing three different fuels. Use theheadings below to help you.

Comparing three different fuelsWhat I wanted to find out about the fuels:

I wanted to find out which fuel will be the first to make thewater boil I predicted that … the paraffin would be the first to make thewater boilTo compare the fuels this is what I did:

First … I took three baby food bottles. I poured the sameamount of water into each one.Then … I heated one bottle using a candle. I heated another

bottle using paraffin as a fuel. I used methylated spirits toheat the third bottle.Next… I watched to see when the water boiledFinally … I noticed that the first bottle of water to boil washeated with methylated spirits.This is what I found out about the energy in the three fuels:

I found that … The candle does not have a lot of energybecause it takes a long time to make the water boil. Theparaffin has more energy than the candle because it makesthe water boil more quickly than the candle. The methylatedspirits has the most energy because it boils the water fastest.While I was doing the test, I also found out that:

The candle has a yellow flame, the paraffin has an orangeflame and the methylated spirits has a blue flame. I also foundout that paraffin makes lots of smoke and soot and it smellsvery bad. It causes air pollution and it makes me cough.Another thing I learned …

A candle makes a little bit of smoke and the methylated spiritsdoes not make smoke but it smells bad.

Points for discussion2. After you have written your report, discuss this question with your

group:Do you think the way we compared these three fuels was fair? Givereasons to support your answer. Decide on some ways in which youcould have made the comparison fairer.

Writing a report

paraffin

methylatedspi

rit

Learner task WRITING TASK

16

Comparing three different fuelsActivityAAsssseessssmmeenntt 55


Learners doing the investigation and writing Learners must be able to:their observations k set up the apparatus correctly

k discuss and make observations while they are carrying out the investigations

k write accurately about what they have observed on their recording sheets

k compare the three fuels by making notes of similarities and differences among them. For example; how fast each fuel heats the water and the amount and type of pollution it gives off

k

Writing a report about comparing three The report must:different fuels k be written in the learners’ own words

k contain the relevant information under each sub-heading

k

WaterWire gauze

Tripod stand

Candle

WaterWire gauze

Tripod stand

Spirit burner

Paraffin

Water

Tripod


17

Transport and fuels

1. Display pictures of different vehicles on the board.

2. Explain the following points to learners:k The car, the plane, the taxi and fishing boat all have

engines which make them move.k These engines need fuel.k Inside the engines the fuel burns, and the heat from the

fuel makes the engines work.k This burning process gives off pollution into the air.

3. Hand out the questions and pictures of different vehicles(see appendix 1) for learners to discuss in their groups (Itwould be best to give each group all five pictures)

• Fossil fuels (coal, oil and gas) are non-renewable sources of energy. Wood, sunlight, wind and food are some renewable sources of energy

• Different forms of transport use different fuels• Most vehicles powered by engines, use fossil fuels

Activity 66

Key concepts

Teacher task

18

Looking at different vehicles1. Look at pictures showing different vehicles that people use for

transport 2. Discuss each picture using the following questions:Questions for discussion:

k What energy changes are taking place when this vehicle moves?k What kind of fuel does this vehicle use?k Where does this fuel come from originally?k Will this kind of fuel be available forever as a source of energy here

on Earth? Give reasons for your answer.k When we use this kind of fuel, is it good or bad for the

environment? Give at least two reasons for your answer.3. Complete the table below.

4. Report about one form of transport to the rest of the class.5. Sequence the pictures of vehicles from the one that uses the most

energy to the one that uses the least energy. Write down thesequence.

Most energy to least energy

Aeroplane Boat Taxi, car Horse cart Bicycle

Learner task GROUP

Vehicle used Advantages Disadvantages What fuel Will the fuel always for transport does it use? be available on Earth?

Bicycle Bicycles are cheaper You can only carry The children’s Yes as long as there is than cars. Children small things on a food is the fuel. enough food for theand adults can use bicycle. You can’t go children.them. They are easy very fast.to fix. They don’t causepollution. You don’t need to buy fuel.

Motor car It goes very fast. It can You have to buy fuel. Petrol. No. It comes from oil and(taxi) carry many people. It is dangerous if you when all the oil on Earth

don’t know how to is used up we won’t bedrive. It pollutes the air. able to get more.

Fishing boat It can carry many It pollutes the air Diesel. No because it also people and many fish. comes from oil.

Aeroplane It can carry many It is very noisy and it Aeroplane fuel No because it also people and goes fast. also pollutes the air comes from oil.

Horse cart It is safer than a car. It is slow compared to Horse food Yes, as long as we canYou can carry things a car. The horse could (grass). grow more food foron it. You don’t have get sick and die the horse.to buy fuel.

Comparing different vehicles and their fuels

It saves

petrol!

19

1. Put the pictures on the board while learners report back. Take only onereport back for each form of transport. Encourage learners to makecorrections to their table as they listen to other groups.

2. After the learners have finished reporting to the class, ask them tosequence the vehicles from the one that uses the most energy to theone that uses the least energy.

3. Put the pictures of the vehicles on the board in that sequence.

Teacher task

Oil, coal and gas are natural

Oil, coal and gas are natural sources of energy found

in the Earth’s crust. They are sometimes called Fossil

Fuels because they are found between layers of rock

and were formed naturally over millions of years from

dead plants and animals.

How much oil, coal and gas is there?

No one knows how much oil, coal, and gas exists in

the crust of the Earth. We are using up the fossil fuels

very quickly. So mining companies are searching all

the time to find new supplies of these natural fuels.

They even have to search in difficult places, for

example, under the sea.

Non-renewable sources of energy

Scientists think that one day soon, we will have

discovered and used up all the Earth’s supplies of

Fossil Fuels. We say that Fossil Fuels are non-

renewable sources of energy. This means that when

they are all used up we can’t get new supplies from

anywhere else. (Because it would take millions of

years for Nature to make more) Scientists estimate

that if we continue using fossil fuels as fast as we are

at present, then all the coal will be finished in 2085.

All the oil will be finished up in 2030.

Renewable sources of energy

There are other sources of energy found in Nature.

For example, we can use sunlight to grow plants and

we can get fuel for our bodies when we eat the plants.

We grow more plants all the time so that our supply of

food for our bodies is never used up. We can burn

wood for fuel to heat our homes. We grow more wood

all the time so that our supply is never used up. We

say that food and wood from plants are renewable

sources of energy. This is because we can always get

new supplies by growing more. Sunlight and heat

from the sun, wind, and the movement of water are

also renewable forms of energy.

Renewable and non-renewable energy sources

1 2 3

4

5

4. Read the following passage to the learners and assist them to understand it.

20

5. Assist learners to complete the following summary:

Renewable and non-renewable sources of energy1 In your own words write to explain what the following words mean:

k A renewable source of energy means that we can make (or get)more of it in the future

k An example of a renewable source of energy is wood or solarenergy

k A non-renewable source of energy means that we cannot make anymore after it is all used up

k An example of a non-renewable source of energy is coal and oiland gas

Transport and fuels

Learner task



Answering the questions: The answers must be correct:

1. All vehicles change stored energy to movement energy.2. The motor car uses petrol or diesel fuel; the aeroplane uses

aviation or jet fuel; the fishing boat uses diesel; the bicycleuses the children’s movement energy, which they got from theenergy stored in their food; the horse cart uses the movementenergy of the horse, which it got from the stored energy in itsfood.

3. The petrol, diesel and jet fuel come from crude oil. Thechildren’s and horses’ food comes from plants and animals.

4. Petrol, diesel and jet fuel will not always be available. Sooneror later all our supplies of oil and gas on Earth will be used up.Food will always be available as long as we keep growing more of it.

5. Petrol, diesel and jet fuel are bad for the environment becausethey give off smoke and other poisonous gases, which pollutethe air. When it rains, this pollution also goes into the water.

6. Food for the children and the horse have no bad effects on theenvironment. The dung from the horses and the toilet wastefrom the children can be returned to the soil and used toenrich it.

Completing a table to The learners must write:compare the advantages k some advantages and disadvantages of each kind of transportand disadvantages of k that the fuel for the horse cart and the bicycle is food, and isdifferent kinds of transport renewable.(We can grow more food)

k that the fuels for the car, the aeroplane fuel and the diesel for the boat are non-renewable.(These fuels will not be available forever)

21

Why do fuels cost money?

1. Tell learners that they are going to find out how the price of crude oil isdetermined. They are also going to think about the factors thatinfluence the price of fuels, which come from crude oil.

2. Write the following questions on the board.

3. Read the article ‘How much does crude oil cost?’ with the learners.Explain any difficult words and concepts.

4. Hold a class discussion to make sure that learners have found theanswers to these questions from the reading.

• All fuels cost money to buy• The price we pay for a fuel includes the cost of the crude oil from

which it was made, as well as the cost of producing it, transporting it and preparing it for sale

• The price of fuels increases when the cost of crude oil increases or when any of the above costs increase

Activity 77

Key concepts

Teacher task

Who decides on theprice of crude oil?

What is OPEC?

How does OPEC decide theprice of crude oil?

How much doescrude oil cost?

Why does the price of crudeoil affect the price of fuels

that we use every day?

How much does crude oil cost?Almost all the energy in the world comes from Fossil Fuels.k Most of the coal is used to produce electricity in power stations.k All of the crude oil is used to produce fuels for transport e.g. petrol, diesel

and aeroplane fuel.Only a few countries in the world have large natural deposits of oil. These

are countries such as Saudi Arabia, Iran, Iraq and Nigeria. They are calledthe ‘Oil Producing and Exporting Countries’ (OPEC). They own the oildeposits in their countries and they supervise the exploration, mining,transporting and selling of oil to countries that do not have their ownoil. Usually it is sold to other countries as crude oil and these countriesthen have to refine it themselves to make fuels.

The OPEC countries together decide on the amount of crude oil forsale and it’s price. The price is always announced as the price per barrelin American Dollars, for example; the price of crude oil is about $25 perbarrel. But this price of crude oil around the world changes slightly every

day depending on howmuch is sold and whichcountries are buying it.

Each country that buys oil pays for the oil andthen pays to have it refined and made into fuels.Some of these costs are:

k the cost of refining it into different fuelsk the cost of transporting and supplying the

fuels to the people who use itk the cost of building petrol stations

After that each country alsoadds some taxes to the price

of the fuel.All these costs are

included in the price of the fuel that we buy.

In South Africa, some newspapers (e.g. The Star,The Cape Times, The Mercury and The Pretoria News)

publish the price of Crude Oil each day. They also publish theprice of important metals like Gold, Silver and Copper.

22

5. For homework ask learners to find out the price per litre of: k paraffink motor car oilk petrolk diesel fuel

6. The next day, hand out the task card called ‘The price of fuel’.

23

The price of fuelExample calculation1. Look at the business report from the Newspaper for Monday

27 August 2001, on page 25.2. Find the price of crude oil and the Dollar/Rand exchange rate.

The price of crude oil shown is the price for one barrel. Each barrelcontains about 200 litres of crude oil.

How much does a barrel of oil cost in South African Rand?

Price of one barrel of oil = $25.71.(US dollars.)

Read to find out how many Rands make 1 Dollar.

1 Dollar = 8.3725 Rand

Therefore: The price of a barrel of crude oil is

$25.71 x 8.3725 = R 215.25

but 1 barrel of crude oil = 200 litres

Therefore: 200 litres of crude oil = R215.25Therefore: the price of 1 litre of crude oil = R 215.25 ÷ 200

1 litre of crude oil costs R1.07

This was the price of everyday fuels on the 27 August 2001:Prices:k 1 litre of petrol cost R 3.63k 1 litre of motor car oil cost R13.60 (500ml cost 6.80)k 1 litre of paraffin cost R 3.80k 1 litre of diesel cost R 3.38

Task1. Look in the business section of today’s newspaper. Find the price of

crude oil and the Dollar/Rand exchange rate.2. Calculate the price for one litre of crude oil today.3. Find out the prices of petrol, motor car oil, paraffin and diesel for

today4. Compare these with the price on the 27th August 2001. Has the oil

price changed? Has the price of fuels changed?5. Why do you think the price of fuels is so much more expensive than

the price of crude oil? Why do you think the price of fuel changes nowand again? Write to explain why.

Learner task

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The price of fuelThe price of fuels changes every now and then because the price ofcrude oil changes. The Dollar/ Rand exchange rate also changes. Boththese things affect the price of fuels. Fuels are much more expensive thancrude oil. Why? Give at least two reasons.

Reason 1The fuels come from crude oil. But the crude oil has to be refined inorder to make it into a fuel. The refining costs money. The cost ofrefining a barrel of oil is added to the price we pay for the fuel. So fuelscost more.Reason 2After the fuel has been made, it has to be transported to petrol stationsand shops to be sold. This also costs money. The cost of transporting the fuel is added to the price we pay for the fuel.Reason 3The government adds taxes to the fuel price.

Why do fuels cost money?Activity

AAsssseessssmmeenntt 77



Learner writing task about The writing must explain that fuels are more expensive thanwhy fuels are more crude oil because:expensive than crude oil k It costs money to transport crude oil to a refinery

k At the refinery the crude oil is heated in order to separate it into different fuels. It is expensive to build and maintain refineries. It is also expensive to heat the crude oil.

k After it is refined the different fuels have to be transported to places where they will be used. The vehicles and pipes for this cost money.

k Then the fuel is sold. It costs money to distribute it and to keep account of how much is bought and sold.

k Many people are employed to get fuels to the places where they are needed . It costs money to pay them.

k All these costs are added on to the price of the fuel.

k The government also adds taxes to the price of fuels.

k

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Activity 88 Fuels and the future1. Facilitate a discussion with the whole class about the following

questions:What will happen when all the oil, coal and gas supplies arefinished on Earth?k Scientists think that in 2030 there will be no more oil and in 2085

there will be no more coal left on earth. What will happen whenthese sources of energy are finished?

k In what ways will our lives change when the world runs out ofFossil Fuels?

k What will you use for fuel when you are 60?k What do you think your grandchildren will use for fuel in 2085?k What can we do to prepare for a world without Fossil Fuels?

2. During the class discussion, write some of the words and phrasesthat the learners have used (on the board).

3. Find books that have information about alternative sources of energy.For example; solar energy, wind energy, energy from waves, energyfrom plants, etc. Learners can research different ways to get energyfrom these renewable sources in the future.k See ‘Eskom to make use of wind energy’.

Teacher task

The Western Cape’s strong windswill be used as an energy sourcefor electricity. Eskom will build amultimillion -Rand wind powergenerator at the end of the year.This will be the only one inSouth Africa. If all goesaccording to plan it will produceenough electricity to supply 2000homes by the year 2005.It will be built close to the N7highway near Malmesbury. Eightto ten large windmills will beattached to electricity generators.They will be placed on the top ofa hill which gets strong windsalmost all year round.Once the Western Cape windpower generator has been built,scientists will study it to find ways of improving itsdesign. They will also calculate how much theelectricity that is produced by it will cost. If it issuccessful then many more wind generators will be

built in parts of South Africa that get a lot of wind.All over the world there is a need for alternativeenergy sources that do not cause pollution. Windenergy is just one kind of alternative energy source.

Sunday Times 25/2/2001

Eskom to make use of wind energyMultimillion-Rand project in Western Cape will investigate environmentallyfriendly alternative energy source

All over the world there is a need for alternative energy sources …

1. Write half a page on ‘Energy and the Future.’ Explain why we have tofind other sources of energy for the future. Give some examples ofother energy sources.

Energy and the FutureIn the future we will have to find new sources of energy. This is because our supply

of fossil fuels on Earth will be finished. Fossil Fuels come from oil andcoal, that were made in the Earth’s crust millions of years ago.

We say that Fossil Fuels are non-renewable sources of energy. Thismeans that, when we have used up all our Fossil Fuels we cannot

get more from anywhere else.

Almost all fuels that we use today come from Fossil Fuelssuch as coal and crude oil. We use coal to make most ofour electricity. We use crude oil to make petrol, diesel,paraffin aeroplane fuel and candles. We also get paint andplastic and many other chemicals and even clothing fromcrude oil.

In the future, when all the Fossil Fuels have been usedwe will not be able to make electricity. We will also notbe able to make fuels, plastics and chemicals. So wemust get these things from something else. This is why

we must look for other sources of energy and chemicals.

In the future we will have to use other sources of energy.We can use solar power. This is the energy from sunlight. We

can use it to make electricity and to heat water in our homes. We canuse wind power to make electricity and to pump water. We also get energy fromplants. Maybe we will even use sources of energy that have not been discovered yet.

Fuels and the future




Writing about ‘Energy The writing must show that the learners understand that:and the Future’ k the supplies of Fossil Fuels on Earth will most probably be

used up some time this century

k we will not be able to make electricity from Fossil Fuels

k we will not be able to have transport that relies on Fossil Fuels

k we will not have products that are made from oil (such as chemicals , paints, clothing and plastics)

k we will have to find and use other sources of energy such as; wind, sunlight energy, energy from plants, nuclear energy and solar energy

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Suggested workscheme on Energy and ChangePERIOD 1Activity 1

• Learners place energylabels onto pictures (10min)

• Learners write sentencesabout the forms of energy

PERIOD 2

Activity 2

• Teacher introduces thekey words (5 min)

• Learners light candlesand discuss thequestions about theburning candle (15 min)

• Class discussion aboutthe burning candle (15min)

• Learners complete thesummary about energyand burning (5 min)

PERIOD 3

Activity 3

• Teacher and learnersmake a class mindmapabout fuels and theiruses (15 min)

Activity 4

• Learners raise questionsabout oil and gas (15min)

PERIOD 4

Activity 4 (cont)

• Teacher introduces thespecific questions aboutoil and gas (10 min)

• Teacher reads theinformation sheet ‘ Aguide to Oil and Gas inSouth Africa’ andexplains any difficultwords or concepts (30min)

PERIOD 5

Activity 4 (cont)

• Teacher sets the task forthe learners. Each groupchooses 2 or 3 questionsto research (10 min)

• Learners read theinformation sheet (30min)

PERIOD 6

Activity 4 (cont)

• Learners read and thenwrite any information tobe eventually included ontheir poster.

• Learners draw or collectpictures to include ontheir poster (40 min)

PERIOD 7

Activity 4 (cont)

• Learners continue toprepare material for theirposter (40 min )

PERIOD 8

Activity 4 (cont)

• Learners put theirpictures and writing ontotheir posters

PERIOD 9

Activity 4 (cont)

• Learners present theirposters one group at atime. Teacher assistsgroups to answer anyquestions from the rest ofthe class. (Teacher allowstime for 2 groups topresent in each period)

PERIOD 10

Activity 4 (cont)

• Learners present posters

PERIOD 11

Activity 4 (cont)

• Learners present posters

• Learners display theposters on the wall of theclassroom.

PERIOD 12

Activity 5

• Teacher introduces threedifferent fuels whichcome from crude oil. (5min)

• Learners receiveapparatus and discusshow they will test thethree fuels. They alsomake predictions (10min)

•1Learners carry out thetest and write theirobservations (30 min)

PERIOD 13

Activity 5 (cont)

• Teacher and classdiscuss testing andcomparing the fuels

(15 min)

• Teacher writes andtranslates any key wordsthat learners used whenmaking theirobservations

(15 min)

• Teacher introduces thereport format andexplains what is expectedof the learners

( 10 min)

PERIOD 14

Activity 5 (cont)

• Learners write theirreports

PERIOD 15

Activity 6

• Teacher hands outpictures and writesquestions on thechalkboard. (10 min)

• Learners discuss thepictures and writeanswers to the questions.(15 min)

• Learners complete thetable about theadvantages anddisadvantages ofdifferent forms oftransport

(20 min)

PERIOD 16

Activity 6 (cont)

• Learners report to the class aboutthe advantages anddisadvantages (Each groupreports on one form of transport)

(25 min)

• Class sequences the pictures. (5 min)

• Teacher reads ‘Renewable andnon-renewable energy resources(10 min)

PERIOD 17

Activity 6 (cont)

• Learners complete the summary

(10 min)

Activity 7

• Teacher and learners read thearticle ‘ How much does Crude Oilcost?’ (20 min)

• Learners find out the prices perlitre of other fuels which comefrom Crude Oil (for homework.)

PERIOD 18

Activity 7 (cont)

• Learners complete the task cardon ‘The price of fuel.’

PERIOD 1

Activity 7 (cont)

* Learners write half a page on‘Energy and the Future

( 40 min)

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Activity 22Task Card to photocopy

Burning a candle1. Look at the burning candle, and discuss it with you group using the

questions to help you.

2. Fill in the ‘I think.....’ column in the table below.3. Read the paragraph ‘Energy from a burning candle’ to find the

answers to the questions.4. Now fill in the ‘ I know ...........’ column in the table below using the

correct information from the reading.

Questions• What does a candle need to burn?• What is happening when a candle

burns? • Where did the candle get its energy? • What energy do we get from a

burning candle?

Questions I think … I know …

k What does a candle need in order to burn?

k What is happening when a candle burns?

k Where did the candle get it’s energy from?

k What energy do we get from a burning candle?

Burning a candle

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Task Card to photocopy


1. Set up your apparatus like this:2. Compare what happens when you use three different fuels to boil

water. Use these questions to help you to make your observations

4What colour is the flame?

4Which fuel causes pollution? What kind of pollution does it give off?

4Which fuel is the first to boil the water?3. Write your observations in the table below:

Activity 55

Candle Methylated Spirits Paraffin


WaterWire gauze

Tripod stand

Candle

WaterWire gauze

Tripod stand

Spirit burner

Paraffin

Water

Tripod


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Task card to photocopy

Comparing three different fuels Learner writing task 1 Write a report about comparing three different fuels. Use the headings

below to help you.


Activity 55

What I wanted to find out about the fuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

I predicted that: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

To compare the fuels this is what I did:

First . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Then . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Next . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Finally . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

This is what I found out about the energy in the three fuels:

While I was doing the test:

I found out that . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

I also found out that . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Another thing I learned is . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Points for discussion2 After you have written your report, discuss this question with your group:

Do you think the way we compared these three fuels was fair? Give reasons to support youranswer. Decide on some ways in which you could have made the comparison fairer.

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Transport and fuelsLooking at different vehicles1. Look at the pictures at the back of the book showing different vehicles

that people use for transport 2. Discuss each picture using the following questions.

Questions for discussionk What energy changes are taking place when this vehicle moves?k What kind of fuel does this vehicle use?k Where does this fuel come from originally?k Will this kind of fuel be available forever as a source of energy here

on Earth? Give reasons for your answer.k When we use this kind of fuel, is it good or bad for the

environment? Give at least two reasons for your answer.3. Complete the table below.

4. Report about one form of transport to the rest of the class.5. Sequence the pictures of vehicles from the one that uses the most

energy to the one that uses the least energy. Write down thesequence.

Most energy to least energy

Activity 66

Vehicle used Advantages Disadvantages What fuel does it Will the fuel always for transport use? be available on Earth?

Bicycle

Motor car (taxi)

Fishing boat

Aeroplane

Horse cart

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Why do fuels cost money?

Learner writing task

The price of fuel

The price of fuels changes every now and then because . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fuels are much more expensive than crude oil. Why? Give at least tworeasons.

Reason 1

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Reason 2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Activity 77

Oh no! It’s moreexpensive than aweek ago!

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40

41

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Imithombo yamandla ehlaziyekayonengahlaziyekiyoI oli, amalahle negesi yimithombo yamandla endalo efunyanwakuqweqwe loMhlaba (Earth’s crust). Ngamanye amaxesha ibizwangokuba yi oli eyifosili, kuba ifumaneka kumanqwanqwa amatyeasezantsi phantsi komhlaba kwaye yazenzekela ngokufa kwezityalonezilwanyana kwiminyaka eliwaka-waka eyadlulayo.

Akakho namnye owaziyo ukuba ingakanani na i oli,amalahle negesievela kuqweqwe lomhlaba. Siyisebenzisa le oli iyifosili ngamandlakangangokuba iyaphela. Ngoko inkampani zemigodi zisoloko ngalolonke ixesha zifuna ukufumana indawo ezintsha ezinale oli yendalo.Zidezikhangele nakwindawo ezinqabileyo, umzekelo: phantsi kolwandle.

Abenzululwazi bacinga ukuba ngenye imini,kungekudala siyakuzesizifumanise siyisebenzise yonke le mithombo ye oli.Sithi i oli eyifosilingumthombo wamandla ongenakuhlaziywa. Oku kuthetha ukuba xa ezioli zisetyenziswe zonke asinakho ukufumana imithombo emitsha naphina.(kuba indalo iyakuthatha iminyaka eliwaka-waka ukwenzaenye.)Abenzululwazi bathekelela ukuba, ukuba siyaqhubekekaukusebenzisa le mithombo ngamandla njengoko sisenza ngoku, onkeamalahle ayakube ephelile ngonyaka wama-2085,ne oli iyakube iphelilengonyaka wama-2030.

Ikhona enye imithombo yamandla efumaneka kwindalo. Umzekelo,singasebenzisa ukukhanya kwelanga ukukhulisa izityalo kwaye nathisingafumana amandla xa sisitya ezi zityalo.Sityala izityalo ngalo lonkexesha, ukuze ukutya okondla imizimba yethu kungapheli. sityala imithikhon’ukuze singaphelelwa ziinkuni.Singabasa iinkuni ukwenza shushuemakhaya Sithi ukutya neenkuni ezivela kwizityalo yimi thomboyamandla ehlaziyekayo.Oku kungenxa yokuba singanakho ukufumanaezinye iinkuni nokutya ngokuthi sityale.Ukukhanya nobushushu obuvelaelangeni,umoya namandla okubaleka kwamanzi yenye yemithomboyamandla ehlaziyekayo.

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Ixabiseke kangakanani I-Oli ekrwada?Phantse onke amandla kwilizwe lonke avele kwifosili umz:amalahle.• Inxalenye yamalahle isetyenziswa ekuveliseni umbane osuka

kwizikhululo zombane.• Yonke Ii-oli ekrwada isetyenziswa ekuveliseni amafutha

ezithuthi,umz:ipetroli,idizili namafutha enqwelo-moya.

Ambalwa kakhulu amazwe apha ehlabathini athi abe nemveliso ye-oli.La ngamazwe afana ne Saudi Arabia,iIrani,neNigeria.Abizwangokuba ngamazwe avelisa i-oli nayithengisa kumazwe angaphandle-OPEC (Oil Producing and Exporting Countries.) La ngamazweanemigodi ye-oli aze ajongane nokombiwa, ukuhanjiswa, kwanokuthengiswa kwayo kumazwe angena oli. Kumaxesha amaninziithengiselwa amanye amazwe iyi oli engacolwanga ukuze wona lamazwe azicolele ukuzenzela amafutha.

Xa edibene la mazwe eOPEC athi agqibe ngamaxabiso entengiso e-oliekrwada kwa nemayithengiswe .Ixabiso lisoloko lisaziwa ngokwexabisolebhareli yeDola yaseMerika.Umzekelo;ixabiso le oli ekrwada lingama$25 ngebhareli, kodwa eli xabiso le oli ekrwada litshintsha mihla le,njekancinci kwilizwe jikelele ngokuxhomekeka okokuba kuthengiswekangakanani na kwaye ngawaphi na amzwe ayithengayo.

Ilizwe ngalinye elithenga le oli, lithi lihlawulele ukucolwa kwayo yenziweamafutha. Amanye amaxabiso ngala:

• Ixabiso lokuyijika le oli ibe zindidi zamafutha• Ixabiso lokuwathatha nokuwasa la mafutha kubantu

abawasebenzisayo• Ixabiso lokwakha izikhululo zeprtroli

Emva koko ilizwe ngalinye nalo longeza eyalo irhafu kwixabisolamafutha alo.Onke la maxabiso adityaniswa kwixabiso lamafuthaesiwathengayo.

Emzantsi Afrika amanye amaphepha (umz: The Star,Cape Times,Mercury, nePretoria News) athi apapashe ixabiso le oli ekrwada rhoqongosuku. Athi kwakhona apapashe ixabiso lezimbiwa ezibalulekileyoezinjenge Golide, iSilivere, neKopa.

Documents

Energy and Change [Grade 7 English]