Question

Ozone in the stratosphere is deleted by :

• A. CF2Cl2
• B. C7F16
• C. C6H6Cl6
• D. C6F6

Answer 1

Answer: (A)

CF2Cl2

Answer 2

Chlorofluorocarbons (CFCs or freons like CF2Cl2) are responsible for depletion of the ozone layer in the upper strata of atmosphere. They are stable and inert compounds. They absorb UV rays and break down liberating free atomic chlorine which causes depletion of ozone through free radical reaction.

$\overset{\bullet}{C}l$ + O3 $\rightarrow Cl\overset{\bullet}{O}$ + O2

$Cl\overset{\bullet}{O}$+ O3 $\overset{\bullet}{C}l$ + 2O2