UGC NET Questions (Paper – 1)

Power plants, industries and vehicles emit sulphur dioxide and nitrogen oxides into the atmosphere. These gases are oxidised to sulphuric and nitric acids, which can be deposited with rain, snow or dust. Acidic deposition lowers the pH of soils and water bodies, damaging forests, aquatic life and buildings. Hence, control of SO₂ and NOx is central to acid rain mitigation.

Option A:
Option A is incorrect because carbon monoxide and ozone are associated more with urban smog and health impacts than with acid deposition.

Option B:
Option B is correct since SO₂ and NOx are the main precursors that form strong acids responsible for acid rain.

Option C:
Option C is incorrect as methane and CFCs are important greenhouse and ozone-depleting gases respectively, but they are not primary acid rain precursors.

Option D:
Option D is incorrect because argon and helium are inert gases that do not form such acids.