Question

How is ozone layer formed in our atmosphere? State one important role of ozone in our atmosphere. What is responsible for its depletion?

Accepted Answer

1. **Formation:** High energy UV radiation splits oxygen molecules ($ ext{O}_2$) into free oxygen atoms ($ ext{O}$). These atomic oxygen atoms combine with molecular oxygen to form ozone ($ ext{O}_3$): $$	ext{O}_2 \xrightarrow{	ext{UV}} 	ext{O} + 	ext{O}$$ $$	ext{O} + 	ext{O}_2 ightarrow 	ext{O}_3$$ 2. **Role:** It shields the surface of the Earth from harmful ultraviolet (UV) radiations from the sun. 3. **Depletion:** Synthetic chemicals like Chlorofluorocarbons (CFCs) are primarily responsible for its depletion.

Ozone layer formation, role and depletion

Explanation

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