The proposed mechanism for a reaction is O2 => 2 O SlowO + NO => NO2 Fast Which of the following would be a rate law for the reaction as proposed?

Question

A. rate = k[O2]

B. rate = k[NO][O2]

C. rate = k[O][O2]

D. rate = k[NO][O]

E. rate = k[NO2][O2

Answer 1

The rate of any reaction generally depends on which step within the reaction is the slowest. This is referred to as the "rate-determining step". In this problem, the first step is the slow step and thus would determine the overall rate of this reaction. Therefore, the rate law for this reaction will be A.