The gases released due to combustion of fossil fuels are SO2,NO2,CO2, these gases remain suspended in the air. When it rains the rain water mixes with these gases to form sulphuric acid, nitrous acid, carbonic acid and comes down on the surface of the earth in the form of acid rain.
Harmful effects of acid rain:
1. It corrodes statues, monuments of marble, building etc.
2. It makes the soil acidic.
3. It damages crops, plantations.