Here's how it works:
* Sulfur dioxide (SO2) is released primarily from burning fossil fuels (like coal and oil) in power plants and industrial processes.
* Nitrogen oxides (NOx) are released from vehicle exhaust and industrial processes.
When these gases are released into the atmosphere, they react with water, oxygen, and other chemicals to form sulfuric acid (H2SO4) and nitric acid (HNO3). These acids then dissolve in rainwater, making it acidic.
So, while rainwater is naturally slightly acidic due to dissolved carbon dioxide (forming carbonic acid), the presence of sulfur dioxide and nitrogen oxides significantly increases its acidity, leading to acid rain.
