In the chlorine chain, the steps are Cl + O3 -> ClO + O2 and ClO + O -> Cl + O2. The net reaction obtained by adding them is

JEE Main levelSingle correct optionDifficulty 2 of 3ev067

In the chlorine chain, the steps are $Cl + O X_{3} ClO + O X_{2}$ and $ClO + O Cl + O X_{2}$ . The net reaction obtained by adding them is

Add the two steps:

Cl + O X_{3} + ClO + O ClO + O X_{2} + Cl + O X_{2}

. Cl and ClO appear on both sides and cancel, leaving

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

. Cl is a catalyst and ClO an intermediate.