Consider the following: 1. Oxides of Hydrogen 2. Oxides of Nitrogen 3. Oxides of Sulphur Which of the above causes/cause acid rain ?

Oxides of nitrogen (NOx) and oxides of sulfur (SOx) are the primary precursors of acid rain: they are emitted into the atmosphere and undergo chemical transformations to form strong acids. Nitrogen oxides and sulfur dioxide react with atmospheric oxidants and water to produce nitric acid (HNO3) and sulfuric acid (H2SO4), which mix with precipitation and fall as acid deposition [2]. Textbook descriptions explicitly identify nitrogen and sulfur oxides as the main gases involved in acid‑rain formation and describe the oxidation pathways that yield these acids [3]. “Oxides of hydrogen” refers effectively to water (H2O) and is not treated as a pollutant that generates acid rain in the cited sources; therefore only 2 and 3 cause acid rain.

Sources

1. [1] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 6: Environmental Degradation and Management > Acidification > p. 8
2. [2] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > 5.15.4. Chemistry of Acid Rain > p. 103
3. [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 6: Geomorphic Movements > Anthropogenic Solution Weathering > p. 90