Question

What role does UV radiation play in the formation of the ozone layer? Explain the process with relevant chemical reactions. Why is the excessive use of CFCs (Chlorofluorocarbons) a cause of concern for organisms?

Accepted Answer

UV splits O2 into O atoms which combine with O2 to form ozone. CFCs deplete ozone, increasing UV radiation that causes skin cancer and tissue damage.. **Role of UV radiation in Ozone formation:** High energy UV radiation splits molecular oxygen ($O_2$) into free oxygen atoms ($O$): $$O_2 \xrightarrow{UV} O + O$$ These free oxygen atoms combine with molecular oxygen to form ozone ($O_3$): $$O + O_2 \rightarrow O_3$$ **Concern regarding excessive use of CFCs:** - CFCs rise into the stratosphere and release chlorine radicals under UV radiation, which catalyze the destruction of the ozone layer. - Depletion of ozone allows harmful UV-B radiation to reach the Earth's surface, leading to skin cancer, eye cataracts, and damage to crops and immune systems.

Ozone Layer Formation and CFCs

Explanation

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