Answer. The ozone molecule absorbs solar radiations and dissociate readily, i.e., self dissociation of ozone takes place. However chlorofluorocarbons (CFCs) (used as refrigerants in air conditioners! and refrigerators) are major cause of depletion of ozone layer. These compounds leak in one way or other; escape and diffuse to stratosphere. There ultraviolet radiations break the C-C1 bond in CFCl3 and generate chlorine free radicals as
CFCl3 CFCl2+Cr
These free radicals are very reactive. They react with ozone to form oxygen as;
O3+ Cl O2 + OCl·
OCl· O· + Cl·
O· + O· O2
A single chlorine free radical released by the decomposition of CFCs is capable of destroying up to 1 lac ozone molecules.