Question

Which of the following are mainly responsible for ozone depletion?
A. Chlorofluorocarbons
B. Hydrocarbons
C. Carbon monoxide
D. Carbon dioxide

Answer 1

Ozone layer protects the earth from harmful ultraviolet radiations that come from the sun. UV rays are harmful to living beings. Its exposure may lead to skin cancer. The ozone layer acts as an umbrella. The ozone layer is present in the stratosphere layer of the atmosphere.

Complete answer: Ozone layer depletion is actually the thinning of the ozone layer in the atmosphere. It is caused by the emission of gaseous bromine or chlorine by human activities. Chlorofluorocarbons (CFC) are mainly responsible for ozone layer depletion. CFC is a gaseous compound made up of carbon, fluorine and chlorine. It is produced by air conditioners, refrigerators, packaging and insulation. The ozone hole was first discovered in Halley Bay, Antarctica in 1981-1983 periods British Antarctic survey. Carbon monoxide has a greater affinity toward oxygen than carbon dioxide. Our atmosphere has 4 layers: troposphere, stratosphere, mesosphere and thermosphere. The average thickness of the ozone layer is 300 Dobson. The thickness of the ozone layer differs worldwide. The ozone layer is thicker at near the poles and thinner at near the equator.
Hence, the correct option is A.

Note: World ozone day is celebrated on 16th September; on this day in 1987, the Montreal Protocol was signed. Montreal Protocol was an international treaty signed between various countries to stop the production of those substances which cause ozone layer depletion. World Ozone day is celebrated to spread awareness for ozone layer depletion.