Question

Acid rain occur when atmosphere is heavily polluted with

Answer 1

Acid rain occurs due to the presence of sulphur dioxide and nitrogen oxides in the atmosphere.

Explanation:

• As we all know that normal rain turns to acid rain when its pH becomes lower than the neutral value of 14 e.g. 4.2-4.4.

• It happens due to the presence of sulphuric acid and nitric acid in the rain.

• Both of these acids are the result of the reaction of sulphur dioxide and nitrogen oxides with water.

Mechanism of acid rain is

• CO2(g) + H2O(l) ⇌ H2CO3(aq) ⇌ H+(aq) + HCO3−(aq)

• N2(g) + O2(g) → 2NO(g)

• 2NO2(g) + H2O(l) → HNO2(aq) + HNO3(aq)

• 2N2(g) + 5O2(g) + 2H2O(l) → 4HNO3(aq)