Part 1 of Essay
The beginning of the (chlorofluorocarbons) era started in 1928, when ' were invented by a Du Pont chemist. ' were best known as "freons" and became famous as a safe, nonflammable refrigerant. It's invention became a great triumph when Freon took the place of sulfur dioxide or ammonia which was used as the working liquid in ....

Part 2 of Essay
.... ultraviolet radiation from the sun. This radiation is the one which would not reach the lower atmosphere in large amounts because of the ozone layer. When these s do brake down, they released atomic chlorine which then would react with the ozone and convert it back into plain oxygen. The even worse part of all this is that these chlorine molecules do not become inactive after the first reaction with the ozone and would be available to destroy more ozone molecules. Thus this process would be the funct ....