Write notes on : Acid rain

Explanation

(i) The term acid rain was given by Robert Angus Smith. It is rainfall with a pH of less than `5.65`.
(ii) Acid rain is a mixture of `H_(2)SO_(4)` and `HNO_(3)` and the ratio of the two may vary depending on the relative quantities of oxides of sulphur and nitrogen emitted. On an average `60-70%` of acidity is ascribed to `H_(2)SO_(4)` and `30-40%` to `HNO_(3)`.
(iii) It damages foliage and growing points of plants. Causes leaching of essential minerals of soil like Ca, Mg, `NO_(3)^(-)` and `SO_(4)^(-2)` .