Nitrogen dioxide, sulphur dioxides are the pollutants which react with the water vapour present in atmosphere to form sulphuric acid and nitric acid. These acids come down with the rain, making the rain acidic. This is called acid rain.

Following are the affects of acid rain:

• It increases corrosion of metals.
• It damages buildings and sculptural materials.
• It removes the basic nutrients such as calcium from the soil.
• It causes direct damage to plants and crops.
• It causes skin eruptions in human being.