Q.8.Explain why: (a) An antacid tablet is taken when you suffer from acidity. (b) Calamine solution is applied on the skin when an ant bites. (c) Factory waste is neutralised before disposing it into the water bodies.

(a) We take an antacid such as milk of magnesia to neutralises the excessive acid released in stomach. (b) Ant injects an acidic liquid (Formic acid) into the skin on biting which causes inflammation, to the skin. The effect of the acid can be neutralised by rubbing. Calamine solution which contains zinc carbonate which is very weak base and causes no harm to the skin. (c) The wastes of factories contain acids. If acids are disposed off in the water body, the acids will harm the organisms. So factory wastes are neutralised by adding basic substances.