JEE Main levelSingle correct optionDifficulty 2 of 3ev071
Assertion (A): CFCs can destroy stratospheric ozone although they are chemically very unreactive near the ground.
Reason (R): Being stable and insoluble, CFCs survive transport to the stratosphere where short-wavelength UV photolyses them to release Cl atoms.
ABoth A and R are true and R is the correct explanation of A
BBoth A and R are true but R is not the correct explanation of A
CA is true but R is false
DA is false but R is true
Answer: A
CFCs are unreactive and insoluble, so they are not removed in the troposphere and slowly reach the stratosphere. There intense UV breaks a C-Cl bond and releases Cl. So R correctly explains A.