Acid rain means rain or any other form of precipitation that is highly acidic in nature, acid rain possesses elevated levels of hydrogen ions. It can have harmful effects on plants, land and aquatic animals and infrastructure.
Acid rains are caused by emissions of sulfur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acid. The government has made efforts since the 1970s to reduce the release of sulfur dioxide and nitrogen oxide into the atmosphere with positive results.
Nitrogen oxides can also be produced naturally by lightning, and sulfur dioxide is also produced by volcanic eruptions. The chemicals in the acid rain can cause paint to peel, can cause corrosion of steel structures such as bridges, and weathering of stone buildings and statues.