is a form of air pollution which is the cause of a lot of environmental damage now and in the past. It is formed when oxides of sulfur and nitrogen combine whith atmospheric moisture in a result it forms sulfuric (so2) and nitric (Nox) acids. What affects when it hits the surface is a lot, for example kills more than 600 million trees a year. Also in Northern Europe has worn away buildings, killed crops, and threatened to polish off the fish life in freshwater lakes. Also, it has damaged 34 percent of West Germany's forests. In the united ....