Answer: Leaching of toxic metal ions and lowering of soil and water pH.
- A A rise in soil pH making it alkaline
- B Leaching of toxic metal ions and lowering of soil and water pH
- C An increase in dissolved oxygen of lakes
- D Precipitation of atmospheric nitrogen as solid nitrates only
Correct answer: B. Leaching of toxic metal ions and lowering of soil and water pH
Explanation: Acid rain lowers the pH of soil and water and mobilises (leaches) toxic metal ions such as aluminium, harming plants and aquatic life.
Classical smog is a reducing mixture of SO₂ and fog, while photochemical smog is an oxidising mixture generated by UV-driven reactions of NOx and hydrocarbons.
Concept context
Understand how human activities alter the atmosphere, water, and soil. Covers air pollutants, smog types, ozone depletion, acid rain, greenhouse effect, water and soil pollution, and the principles of green chemistry.