Which two constituents are the most important components of acid rain?

Which two constituents are the most important components of acid rain?

• A. SO2 and NOx
• B. CO2 and CH4
• C. O3 and NO2
• D. SO3 and NO

Answer: (A)

Acid rain forms when sulfur dioxide and nitrogen oxides released from burning fossil fuels react in the atmosphere to produce sulfuric and nitric acids, which then fall with rain. These two pollutants are the primary sources that drive the formation of the acids responsible for acid rain, making them the most important constituents. Sulfur dioxide is emitted and oxidizes to sulfuric acid, while nitrogen oxides lead to nitric acid through atmospheric reactions. Other options mix in greenhouse gases or reactive species that aren’t the main acid-forming precursors, so they don’t explain acid rain as directly.

Acid rain forms when sulfur dioxide and nitrogen oxides released from burning fossil fuels react in the atmosphere to produce sulfuric and nitric acids, which then fall with rain. These two pollutants are the primary sources that drive the formation of the acids responsible for acid rain, making them the most important constituents. Sulfur dioxide is emitted and oxidizes to sulfuric acid, while nitrogen oxides lead to nitric acid through atmospheric reactions. Other options mix in greenhouse gases or reactive species that aren’t the main acid-forming precursors, so they don’t explain acid rain as directly.