Which gas is most commonly responsible for causing acid rain?

The gas most commonly responsible for causing acid rain is sulfur dioxide. This compound is primarily produced from the burning of fossil fuels, such as coal and oil, which release sulfur oxides into the atmosphere. When sulfur dioxide enters the atmosphere, it can be oxidized and subsequently reacts with water vapor, oxygen, and other trace chemicals to form sulfuric acid. This acid is then deposited back to the Earth's surface through precipitation, leading to acid rain.

Acid rain has significant environmental impacts, including harming aquatic ecosystems, damaging vegetation, and contributing to the deterioration of buildings and monuments. The formation of acid rain is a prime example of how human activities, particularly industrial processes, can lead to environmental degradation through atmospheric chemical reactions.

While nitrogen dioxide and carbon dioxide can also affect environmental conditions, they do not play a direct role in the formation of acid rain to the extent that sulfur dioxide does. Nitrogen dioxide does contribute to the formation of nitric acid, which can lead to acid rain, but it is not as significant as sulfur dioxide. Ozone is a different type of pollutant that affects air quality but does not contribute to acid rain formation.