Acid rain is an environmental problem that knows no boundaries. Increasing acidity in natural waters and soil has become a global concern. Acidification and climate change are interrelated, as the sources responsible for acidification of environment and green house gases are same. Normally unpolluted rain water is always slightly acidic, because CO, in atmosphere dissolve in it forming carbonic acid H2CO3 the pH of unpolluted rain water is about 5.5-5.7. But due to presence of S02 and NO, gases as pollutants in the atmosphere, the pH of rain is further lowered. Often as low as 2.4 and this type of precipitation is generally referred to as acid rain.