On the basis of chemical reactions involved, explain how do CFC's cause depletion of ozone layer in stratosphere ?

Explanation

In the presence of uv radiation, CFC's break up into chlorine free radical.
`CF_(2) Cl_(2) overset(hv)(rarr) .CF_(2) Cl+ Cl.`
`CFCl_(3) overset(hv)(rarr) .CFCl(2)+Cl.`
`Cl. + O_(3) rarr ClO. + O_(2)`
`ClO. + O rarr Cl. +O_(2)`
Chlorine radical is regenerated in the course of reaction. Due to this continuous attack of `Cl^(@)` thinning of ozone layer takes place which leads to formation of ozone hole.