Ncert Exercises & Solutions

The acids present in acid rain are :

a. Peroxyacetylnitrate

b. H₂CO₃

c. HNO₃

d. H₂SO₄

Choose the correct option :

1. (a, b)
2. (b, c)
3. (c, d)
4. (a, d)

HINT: Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air.

Explanation:

CO₂ is slightly soluble in water forming carbonic acid.

{CO}_{2} + H_{2} O \to H_{2} {CO}_{3}

The oxides of nitrogen undergo oxidation reaction followed by reaction with water vapour form nitric acid.

NO + O_{2} \to 2 {NO}_{2}

2 {NO}_{2} + H_{2} O \to {HNO}_{3} + {HNO}_{2}

The oxidation of SO₂ into SO₃ in presence of dust particles or metal ions. SO₃, then with water vapours to form H₂SO₄.

2 {SO}_{2} + O_{2} \to_{or metal ions}^{Dust particles} 2 {SO}_{3}

{SO}_{3} + H_{2} O \to H_{2} {SO}_{4


Because carbonic acid is a relatively weak acid, the ability of carbon dioxide alone to generate true “acid rain” is very limited.}