Acid rain Acid rain Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). It can have harmful effects on plants, aquatic animals and infrastructure. Acid rain is caused by emissions of sulphur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids. Some governments have made efforts since the 1970s to reduce the release of sulphur dioxide and nitrogen oxide into the atmosphere with positive results. Nitrogen oxides can also be produced naturally by lightning strikes, and sulphur dioxide
Environmental impact of the coal industry the environment. While these substances are trace impurities, enough coal is burned that significant amounts of these substances are released. During combustion, the reaction between coal and the air produces oxides of carbon, including carbon dioxide (CO, an important greenhouse gas), oxides of sulfur (mainly sulfur dioxide, SO), and various oxides of nitrogen (NO). Because of the hydrogenous and nitrogenous components of coal, hydrides and nitrides of carbon and sulfur are also produced during the combustion of coal in air. These include hydrogen cyanide (HCN), sulfur nitrate (SNO) and other toxic substances. SO and nitrogen oxide react in the atmosphere