Acid Rain

"Acid Rain,"   or more precisely acidic precipitation, is the term used to describe


rainfall that has a pH level of less than 5.6--a pH of 7 being neutral.   This form of air


pollution is currently a subject of great controversy because of the damage it does tot he


environment and property worldwide.   For the last ten years, this occurrence has brought


destruction to thousands of lakes and streams in the United States, Canada, and parts of


Europe.   It also leads to the deterioration of buildings and statues by reacting with several


minerals. Acid rain is formed when oxides of nitrogen and sulfite combine with moisture


in the atmosphere to make nitric and sulfuric acids.   These acids can be carried away far


from its origin.  


The two primary sources of acid rain are sulfur dioxide (SO2), and oxides of nitrogen


(NOx). Sulfur dioxide is a colorless gas released as a by-product of combusted fossil fuels


containing sulfur (Farnham, http://www.ems.psu.edu/info/explore/AcidRain.html). A


variety of industrial processes, such as the production of iron and steel, utility factories,


and crude oil processing produce this gas. Sulfur dioxide can also be emitted into the


atmosphere by natural disasters or means (Farnham,


http://www.ems.psu.edu/info/explore/AcidRain.html). This accounts for ten percent of all


sulfur dioxide emission,   coming from volcanoes, sea spray, plankton, and rotting


vegetation. Overall, 69.4 percent of sulfur dioxide is produced by industrial combustion.


Only 3.7 percent is caused by transportation (Farnham,


http://www.ems.psu.edu/info/explore/AcidRain.html).


The other chemical that is also chiefly responsible for the make-up of acid rain is


nitrogen oxide. Oxides of nitrogen is a term used to describe any compound of nitrogen


with any amount of oxygen atoms....