Abstract

Acid rain is a phenomenon of serious environmental concern. By definition, acid rain refers to rainwater that is acidic. But in reality, it is more accurate to use the term acid deposition since not only rain but also snow, sleet, hail, and even fog can become acidic. In addition to the process where acids become associated with precipitation (called wet deposition), acid gases and particles can also be deposited on the Earth’s surface directly (called dry deposition). However, since the name “acid rain” has become a household term and its formation is better understood than other types of acid deposition, the following discussions will focus on acid rain.