GATE Air and Noise Pollution: Gaseous Pollutants – Previous Year Questions

3 GATE previous year questions on Gaseous Pollutants (Air and Noise Pollution, Environmental Science and Engineering) with answers and explanations, from every paper.

1. GATE 2022 ES Q23 (1 mark, Multiple choice) – Which is the most common raw material in flue-gas desulfurization?
2. GATE 2024 ES Q30 (1 mark, Multiple select) – Which are secondary air pollutants?
3. GATE 2025 ES Q59 (2 marks, Numerical answer) – A boiler burns1 kg/s coal containing3% sulfur. Assume all sulfur becomes SO₂ and no sulfur remains in ash. Find SO₂ emissions in integer kg/day.