Question

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

Accepted Answer

0. 1. **Formation:** High-energy UV radiation splits molecular oxygen ($O_2$) into free oxygen atoms ($O$). These free atoms combine with molecular oxygen to form ozone ($O_3$): $$O_2 \xrightarrow{UV} O + O$$ $$O + O_2 \rightarrow O_3$$ 2. **Role:** It shields the surface of the Earth from harmful ultraviolet (UV) radiation emitted by the Sun. 3. **Depletion:** Chlorofluorocarbons (CFCs) used in refrigerants and fire extinguishers are primarily responsible for ozone depletion.

Formation and Role of Ozone Layer

Explanation

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