JEE Main levelSingle correct optionDifficulty 2 of 3ev069
The Antarctic ozone loss becomes severe in September-October rather than in the dark midwinter because
Asunlight is needed to photolyse ClX2 and HOCl into chlorine atoms that start the chain
Bozone is formed faster in the dark
CCFCs are produced only in spring
Dpolar stratospheric clouds form only in sunlight
Answer: A
During the polar night the active chlorine accumulates as ClX2 and HOCl on the cloud surfaces, but nothing breaks them. When sunlight returns in spring they photolyse to Cl atoms, which rapidly destroy ozone.