In the polar lower stratosphere the cycle is: 2Cl + 2O3 -> 2ClO + 2O2; ClO + ClO -> Cl2O2; Cl2O2 -> Cl + ClOO; ClOO -> Cl + O2. The net reaction and the number of chlorine atoms regenerated per cycle are

JEE Advanced levelSingle correct optionDifficulty 3 of 3ev093

In the polar lower stratosphere the cycle is: $2 Cl + 2 O X_{3} 2 ClO + 2 O X_{2}$ ; $ClO + ClO Cl X_{2} O X_{2}$ ; $Cl X_{2} O X_{2} Cl + ClOO$ ; $ClOO Cl + O X_{2}$ . The net reaction and the number of chlorine atoms regenerated per cycle are

Step 1 uses 2 ozone and gives 2 ClO + 2

O X_{2}

. The two ClO form

Cl X_{2} O X_{2}

, which gives Cl + ClOO, and ClOO gives Cl +

O X_{2}

. Totals: 2

O X_{3}

consumed,

2 + 1 = 3

O X_{2}

formed, so

2 O X_{3} 3 O X_{2}

. Two Cl atoms used in step 1 are regenerated as Cl + Cl.