Question
What are the reactions involved for ozone layer depletion in the stratosphere?
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Answer
In the stratosphere, ozone is a product of the action of UV radiations on dioxygen as:
eaction (ii) indicates the dynamic equilibrium existing between the production and decomposition of ozone molecules. Any factor that disturbs the equilibrium may cause depletion of ozone layer by its decomposition. One such factor is the release of chlorofluorocarbon compounds (CFCs). These are non-reactive, non-flammable molecules that are used in refrigerators, air conditioners, plastics, and electronic industries. Once released CFCs mix with atmospheric gases and reach the stratosphere, where they are decomposed by UV radiations.
- $\text{CF}_2\text{Cl}_{2(\text{g})}\xrightarrow{ \ \ \ \text{UV} \ \ \ \ }\dot{\text{Cl}}_{(\text{g})}+\dot{\text{CF}}_2\text{Cl}_{\text{(g)}}$
- $\dot{\text{Cl}}_{(\text{g})}+\text{O}_{3(\text{g})}\xrightarrow{\ \ \\ \ \ \ \ \\ \ \ \\ \ \ \\ }\text{Cl}\dot{\text{O}}_{(\text{g})}+\text{O}_{2(\text{g})}$
- $\text{Cl}\dot{\text{O}}_{(\text{g})}+\text{O}_{(\text{g})}\xrightarrow{\ \ \\\ \\\ \ \ \ \ \ }\dot{\text{Cl}}_{(\text{g})}+\text{O}_{2(\text{g})}$
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