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

In general, the slow step is always the rate determining step. For this reaction, the slow step was identified as O2 ==> 2O. I believe that your rate law should be answer choice a. In a two step reaction, you need to consider the variable that is needed to complete the reaction. In this case, the reaction cannot continue without the oxygen component.