Assertion: Ozone is destroyed by CFCs in the upper stratosphere.

Reason: Ozone holes increase the amount of UV radiation reaching the earth.

(1) Assertion and reason are incorrect.

(2) Assertion and reason are both correct, and the reason is the correct explanation for the assertion.

(3) Assertion and reason are correct, but the reason is not the explanation for the assertion.

(4) Assertion is false, but the reason is correct.

Show Answer

CFC’s are responsible for depletion of ozone layer.

$\text{Cl} + \text{O}_3 \xrightarrow{h\nu} \dot{\text{Cl}}(\text{g}) + \text{F}_2\dot{\text{C}}\text{Cl}(\text{g})$

$\dot{\text{Cl}} + \text{O}_3 \longrightarrow \text{ClO}^\cdot(\text{g}) + \text{O}_2(\text{g})$

$\text{ClO}^\cdot + \text{O} \longrightarrow \dot{\text{Cl}} + \text{O}_2(\text{g})$

Due to depletion of ozone layer more UV radiation filters into troposphere.