Which of the following pollutants are most responsible for acid rain…
2024
Which of the following pollutants are most responsible for acid rain formation?
A. Carbon monoxide (CO)
B. Nitrogen dioxide (NO2)
C. Ozone (O3)
D. Sulphur dioxide (SO2)
E. Lead (Pb)
Choose the correct answer from the options given below:
Answer: B. B and D only — ConceptAcid rain forms when atmospheric precursor gases are oxidised and react with water to produce strong acids. The main precursors are sulphur dioxide,…
- A.
A and B only
- B.
B and D only
- C.
C and E only
- D.
A, B and D only
Show answer & explanation
Correct answer: B
Concept
Acid rain forms when atmospheric precursor gases are oxidised and react with water to produce strong acids.
The main precursors are sulphur dioxide, which forms sulphuric acid, and nitrogen oxides, which form nitric acid.
Application
In the given list, nitrogen dioxide (statement B) supplies a nitrogen oxide precursor and sulphur dioxide (statement D) supplies the sulphur oxide precursor. Therefore, the required pair is B and D only.
Contrast
Carbon monoxide mainly oxidises towards carbon dioxide and is not one of the principal acid-rain precursors.
Ozone is a photochemical oxidant, but it is not the principal source gas for sulphuric or nitric acid in acid rain.
Lead is a metallic particulate pollutant rather than a gaseous precursor that forms the principal acids in acid rain.
Cross-check
The chemical pathways agree with the selection: sulphur dioxide is converted to sulphuric acid, while nitrogen dioxide is converted to nitric acid. Hence the result is B and D only.