GED Science TestEarth and Space ScienceMedium
A farmer observes that the soil on their land is becoming increasingly acidic over time, leading to reduced crop yields. They suspect that atmospheric pollution is contributing to this issue. Which atmospheric pollutant is most likely responsible for increasing soil acidity in this scenario?
- AMethane (CH4)
- BOzone (O3)
- CSulfur dioxide (SO2)
- DCarbon dioxide (CO2)
Show answer & explanationAnswer & explanation
Correct answer: C. Sulfur dioxide (SO2)
Sulfur dioxide (SO2) and nitrogen oxides (NOx) are primary precursors to acid rain. When released into the atmosphere, they react with water, oxygen, and other chemicals to form sulfuric and nitric acids, which then fall to Earth as acid rain, increasing soil acidity.
Why the other options are wrong
- A. Methane is a greenhouse gas but does not directly cause acid rain.
- B. Ozone in the troposphere is a pollutant and respiratory irritant but does not directly cause soil acidification.
- D. Carbon dioxide contributes to ocean acidification but is not the primary cause of soil acidification through acid rain.
Acid Rain Precursors
Atmospheric pollutants, primarily sulfur dioxide (SO2) and nitrogen oxides (NOx), that react with water and other chemicals to form acidic compounds that fall to Earth as acid rain.
- Mainly released from burning fossil fuels in power plants and industrial facilities.
- Causes acidification of soils, lakes, and streams.
- Damages forests, crops, and infrastructure.
Memory trick: S-O-2: Sulfur's Sour Soil Solution.