Page 110 - EVS Class 04

Filtration
Solid impurities like dirt and sand can be removed by filtering water. Now-a-

days, ultraviolet purifiers are used to make water pure for drinking.

People use aquaguard or reverse Osmosis system to kill germs in water.

* Harmful chemical wastes from homes and factories, fertilizers, pesticides, sewage
and dead bodies pollute the water.

* Polluted water disturbs the aquatic life killing fish and water plants.
* Polluted water can cause diseases like jaundice, typhoid, dysentery, diarrhoea and
cholera.
* Water which is pure for drinking is called potable water.

* We should be a little careful to conserve water.
* We must make sure that the water we drink is clean.

A. Answer the following questions.

1. How does water get polluted?
2. What are the effects of water pollution?

3. What is rainwater harvesting?

4. How can we make water potable?
5. How is water made pure for drinking?

B. Fill in the blanks.

1. Harmful chemical wastes from _________________ and factories pollute
the water.

2. Water plants become ____________________ and die.

3. Water is ____________________ .
4. ____________________ kills the germs in water.

C. State whether the following statements are right or wrong .

1. We can use river water directly for drinking.

2. We should keep the drinking water covered.

3. Boiling cannot kill the germs present in water.
4. Purifiers kill the germs present in water.

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