Page 189 - ICSE Chemistry 8

4. Potable water should __________________________.
(a) be clear and transparent
(b) contain odour

(c) have dissolved and suspended impuri es
(d) not contain minerals necessary for our body

5. Which of these is the correct sequence of steps of purifi ca on of water obtained from lakes or
rivers?
(a) Sedimenta on Chlorina on Filtra on

(b) Chlorina on Filtra on Sedimenta on
(c) Sedimenta on Filtra on Chlorina on

(d) Filtra on Chlorina on Sedimenta on
6. Which of the following is not an example of a colloid?

(a) Smoke (b) Fog
(c) Sugar mixed with water (d) Milk

E. Write the answer as instructed.

1. Write three uses of water.

2. Name the sources of water.
3. Name the processes by which water is added to the atmosphere.
4. Name the main processes involved in the purifi ca on of water.

5. Write the uses of dis lled water.

6. Name the processes by which water can be purifi ed at home.
7. Name the types of solu on on the basis of the solute dissolved in the solvent.
8. Write the factors aff ec ng the forma on of a solu on.

9. Name the types of solu on on the basis of the size of the solute present in them.

10. Name three hygroscopic substances.

SHORT AND PRECISE

A. Show the given text in the form of fl owcharts.

1. Sources of water
2. Purifi ca on of water

3. Classifi ca on of solu ons on the basis of the size of the solute present in them
4. Causes of hardness of water

B. Give reasons for the following statements.
1. Water is essen al for survival and existence of all living organisms.

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