Question

Acid rain is the result of increase in
1. Dust and microbes in air
2. CO₂ and CO in air
3. SO₂ and NO₂ in air
4. Dust and ozone in air

Answer 1

Correct Answer - Option 3 : SO₂ and NO₂ in air

The correct answer is SO2 and NO2 in air.

• pH of normal rainwater is 5.6 due to the presence of H⁺ ions.
• Normal rainwater becomes acid rain when the pH of the rainwater drops below 5.6.
• Acid rain is the result of the increase in SO₂ and NO₂ in the air.
• Acid rain is a byproduct of a variety of human activities that emit the oxides of sulfur and nitrogen into the atmosphere
• SO2 and NO2 after oxidation and reaction with water are major contributors to acid rain.
  • \(2SO_2 (g) + O_2 (g) + 2H_2O (l) → 2H_2SO_4 (aq) \)
  • \(4NO_2 (g) + O_2 (g)+ 2H_2O (l) → 4HNO_3 (aq)\)

• Acid rain refers to the ways in which acid from the atmosphere is deposited on the earth’s surface.
• It affects plants and animal life in the aquatic ecosystem.
• Acid rain is harmful to agriculture and plants as it dissolves and washes away nutrients needed for their growth.
• Acid rain leads to respiratory ailments in human beings and animals.
• When acid rain falls and flows as groundwater to reach rivers, lakes, etc.
• The Taj Mahal in India has been affected by acid rain.
• Acid rain can be avoided only by reducing the emission of sulfur dioxide and nitrogen dioxide in the atmosphere by controlling human activities.