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LO3: SCIENCE, SOCIETY AND THE ENVIRONMENTThe learner will be able to demonstrate an understanding of the interrelationships between science and technology, society and the environment.

Clean drinking water in the townLots of people live in a town. It is important that there is enough clean water for everyone.

For you to do:Follow the path of a water droplet to see how water is cleaned to make it safe to drink.

Questions to talk about:1.Water is used in many different ways in the city. Name six uses of water in the city. 2.Water is scarce in many parts of South Africa. It is a valuable resource that needs to be used

wisely. List three ways in which you can use water wisely. 3. What would happen to a town if the people did not pay for their tap water?

Intermediate Phase: Natural Sciences

Smelly Science21

MANZI

Rands & SensePAY FOR WATER

I pass through screens to

remove large plants, animals, sticks and litter.

2

I am in a giant giant tank where I spin around and around. Some

chemicals have been added. Sand, plants, animals and some germs stick

to the chemicals to form floc.

3

I am in a large tank. The floc

sinks to the bottom of the tank.

I am cleaner already, but not clean enoughto drink.

4

Almost clean! Now I am flowing through a sand filter to remove the last small plants, animals

and some germs.

5

I am being sprayed with chlorine gas to kill all remaining germs.

I am clean enough to drink!6

I have travelled along many rivers to reach the dam. Along the way, I have picked up many things that make me dirty. I am on my way to the purification

station to be cleaned.

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RANDWATER CHANGES.indd 21 10/9/08 10:20:09