Question

Which of the following statements is correct?

पर्याय

• Ozone hole is a hole formed in stratosphere from which ozone oozes out.

• Ozone hole is a hole formed in the troposphere from which ozone oozes out.

• Ozone hole is thinning of ozone layer of stratosphere at some places.

• Ozone hole means vanishing of ozone layer around the earth completely.

Answer 1

Ozone hole is thinning of ozone layer of stratosphere at some places.

Explanation:

Since it was found that a unique set of conditions were responsible for the ozone hole. In summer, nitrogen dioxide and methane react with chlorine monoxide and chlorine atoms forming chlorine sinks, preventing much ozone depletion, whereas in winter, special types of clouds called polar stratospheric clouds are formed over Antarctica.

Following reactions occur in the stratosphere.

\[\ce{CH2Cl2 -> CF2Cl + \overset{\bullet}{C}l}\]

\[\ce{\overset{\bullet}{C}l + O3 -> Cl\overset{\bullet}{O} + O2}\]

\[\ce{Cl\overset{\bullet}{O} + [O] -> \overset{\bullet}{C}l + O2}\]