Here's a breakdown:

* Sulfur dioxide (SO2): This gas is primarily released from the burning of fossil fuels, particularly coal, in power plants and industrial processes.

* Nitrogen oxides (NOx): These gases are also released from burning fossil fuels, as well as from vehicle exhaust.

When these gases are released into the atmosphere, they react with water, oxygen, and other chemicals to form sulfuric acid and nitric acid. These acids then fall to the ground in the form of rain, snow, fog, or dry particles, causing acid rain.