Answer in brief:

(a) Why is river water unfit for drinking ?

(b) Why is tap water a mixture ?

(c) What is mineral water?

(d) What is the purpose of adding bleaching powder to water supplied to the town?

(e) How is chemically pure water obtained in the laboratory?

(f) How is water in a swimming pool kept free from germs?

(g) Why is water important for plants and animals?

(a) River water is absolutely unfit for drinking directly due to the presence of the impurities like clay, sand particles, organic matter, harmful bacteria, etc.

(b) Tap water is a mixture because it contains dissolved impurities like salts, gases and sometimes chlorine.

(c) Mineral water is purified water that contains dissolved minerals like calcium, magnesium, and potassium, and is safe for drinking.

(d) Bleaching powder as a source of chlorine, is added to kill harmful germs and disinfect the water before it reaches homes.

(e) Chemically pure water is obtained by distillation, where water is boiled, and the steam is condensed, leaving impurities behind.

(f) Swimming pools are usually chlorinated to kill the germs in the pool water.

(g) Water is essential for many life processes in plants and animals like digestion, transport of nutrients, temperature regulation, and photosynthesis (in plants only).