Give reasons for the following observations:

(a) Air holes of a gas burner have to be adjusted when the vessels being heated get blackened by the flame.


(b) Use of synthetic detergents causes pollution of water.

(a) When the bottoms of cooking vessels getting blackened by the flame, it means that the air holes of a gas burner are blocked and fuel is getting wasted. So, the air holes of the gas burner should be adjusted.

(b) Some synthetic detergents cannot be decomposed by micro-organisms as they are non-biodegradable. Hence, they cause water pollution.


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