Final answer:
Coal combustion is the main contributor to acid rain, emitting sulfur dioxide and nitrogen oxides that form sulfuric and nitric acids upon reacting with atmospheric moisture, resulting in precipitation with a low pH harmful to both natural and man-made environments.
Step-by-step explanation:
The primary cause of acid rain in the world is the emissions of sulfur dioxide and nitrogen oxides, which are byproducts of the combustion of fossil fuels.
Coal, in particular, is a significant contributor to these emissions and thus to acid rain. When sulfur dioxide and nitrogen oxides are released into the atmosphere, they can react with water, oxygen, and other chemicals to form sulfuric acid and nitric acid. These acids then mix with cloud moisture and fall as precipitation with a low pH, which is referred to as acid rain.
Acid rain has harmful effects on natural ecosystems, such as lowering the pH of lakes and killing aquatic life, as well as on man-made structures, causing the chemical degradation of iconic monuments like the Lincoln Memorial in Washington, DC. Additionally, acid rain contributes to soil degradation, which can negatively impact plant life and reduce biodiversity.