In the nitric oxide cycle, NO + O3 -> NO2 + O2 followed by NO2 + O -> NO + O2, the species that acts as the catalyst is

JEE Main levelSingle correct optionDifficulty 2 of 3ev076

In the nitric oxide cycle, $NO + O X_{3} NO X_{2} + O X_{2}$ followed by $NO X_{2} + O NO + O X_{2}$ , the species that acts as the catalyst is

NO is consumed in the first step and regenerated in the second, so it is the catalyst.

NO X_{2}

is formed and then consumed, making it an intermediate. Net:

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