What is Acid rain ? What are its harmful effects ?

Explanation

When the rain falls through polluted air, it comes across chemicals such as gaseous oxides of sulphur `(SO_(x))` , oxides of nitrogen (`NO_(x)`) , mist of hydrochloric acids & phosphoric acid etc. These substances dissolve in falling rain making it more acidic than normal with pH ranging between (5.6 - 3.5).
Harmful effect of acid rain
(i) Most of aquatic animals can not survive when pH is less than 4. Certain fishes die even when the pH is less than 5.5.
(ii) Acidic water is dangerous for plants leaf pigments are decolourised , acid affects green pigments of plants. Agricultural productivity is also decreased.
(iii) Metallic surfaces exposed to acid rain are readily corroded. Textile fabrics, paper, & leather products lose their material strength or disintexamplerate by the acid rain.