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

1. **Formation:** High energy UV radiation splits oxygen gas into free oxygen atoms: $$	ext{O}_2 \xrightarrow{	ext{UV}} 	ext{O} + 	ext{O}$$ These free atoms combine with molecular oxygen to form ozone: $$	ext{O} + 	ext{O}_2 ightarrow 	ext{O}_3$$ 2. **CFC Concern:** CFCs deplete the ozone layer by breaking down $	ext{O}_3$, causing ozone hole. This allows harmful UV radiation to reach Earth, causing skin cancer, cataracts, and damage to aquatic and terrestrial ecosystems.

Ozone layer formation and CFCs concern

Explanation

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