Acid rain is formed when moisture in the air combines with nitrogen oxides and sulfur dioxide emitted by factories, power plants andvehicles that burn coal or petroleum products. In interaction with water vapor, these gases form sulfuric acid and nitric acid. Finally, these chemicals fallto earth accompanied the precipitation, forming acid rain.
The primary air pollutants that lead to acid rain can travel great distances, the windmoving them hundreds or thousands of miles before precipitating in the form of dew, rain, rain, hail, snow, fog or mist. When precipitation occurs, cancause great damage to the environment.
The rain usually has a pH of about 5.65 (slightly acidic), due to the presence of atmospheric CO2, which formscarbonic acid, H2CO3. If it is considered acid rain has a pH of less than 5 and can reach the pH of vinegar (pH 3). These pH values are achieved by thepresence of acids such as sulfuric acid, H2SO4 and nitric acid, HNO3. These acids are formed from sulfur dioxide, SO2, and nitrogen monoxide areconverted into acids.
The oil and coal as an energy source used in large quantities, can also produce sulfur and nitrogen oxides and sulfur dioxide emittedby factories, power plants and vehicles that burn coal or petroleum products. In interaction with water vapor, these gases form sulfuric acid and nitricacid. Finally, these chemicals rise into the atmosphere, forming a cloud and fall to earth after accompanying the precipitation, forming acid rain.