MolSynapsequestion bank

MolSynapse / Question bank / Haloalkanes and Haloarenes / Polyhalogen compounds

JEE Main levelSingle correct optionDifficulty 2 of 3hx136

Chlorofluorocarbons cause depletion of stratospheric ozone mainly because ultraviolet radiation breaks $CF X_{2} Cl X_{2}$ to release

Acarbene $CF X_{2}$ , which oxidises $O X_{3}$
Bchlorine free radicals, which catalytically destroy $O X_{3}$
Cfluorine free radicals, which react with $O X_{2}$ forming $O X_{3}$
Dchloride ions, which reduce $O X_{3}$ in water droplets

Answer: B

CF X_{2} Cl X_{2} h ν CF X_{2} Cl \cdot + Cl \cdot

The

Cl \cdot

radical reacts as

Cl \cdot + O X_{3} ClO \cdot + O X_{2}

and

ClO \cdot + O Cl \cdot + O X_{2}

. Cl is regenerated, so one radical destroys many ozone molecules. The

C - F

bond is far stronger and is not broken by the UV available.

Practice Haloalkanes and Haloarenes More on Polyhalogen compounds

Previous questionNext question

More questions on Polyhalogen compounds