Ozone, pronounced OH Zohn, is a form of oxygen that is present in the earth's atmosphere in small amounts. Ozone in the upper atmosphere is a major factor in making life on earth possible. But ozone in the lower atmosphere contributes to air pollution. Ozone is used commercially in water purification process and as a bleaching agent. Ordinary oxygen molecules have two oxygen atoms, ozone has three. Ozone is produced naturally through photochemical and electric …showed first 75 words of 571 total…

…showed last 75 words of 571 total…may eventually thin over more populated areas, endangering human health and harming many plants and animals. Scientist measure changes in ozone in the upper atmosphere with instruments on aircraft, balloons, and satellites. In 1978, the united states government banned fluorocarbon aerosols for most uses . However, the ban did not affect the use of CFC's as refrigerants or in insulation. In 1990, the united states and 55 other nations agreed to end the production of CFC's by the year 2000.