Although the phenomenon of “acid rain” (more correctly acid deposition) was identified in Manchester, England, as long ago as 1852, and described more thoroughly in 1872, modern scientific research has been going on only since the mid-1950s. Public concern about the problem began in the late 1960s. Acid rain is an environmental hazard that is transponder in nature. Northeastern America, North Western Europe and India are facing an acute problem of acid rain. Acid rain has affected certain rivers, lakes, streams and forests in United Kingdom (UK), United States of America (USA), Germany and many other countries.
Acid rain literally means ‘the presence of excessive acids in rain waters’. Acid precipitation is a mixture of strong mineral acids sulphuric acid (H2SO4), nitric acid (HNO3) and in some locations, hydrochloric acid (HCl). It usually has a ph of less than 5.6, the value of distilled water in equilibrium with atmospheric carbon dioxide.