Consider the formation of nitrogen dioxide and oxygen: NO (g) + O3 (g) ⇌NO2 (g) + O2 (g) The reaction is first order in O3 and second order overall. What is the rate law? (A) rate=k[NO]2[O3]2 (B) rate=k[NO][O3]2 (C) rate=k[O3] (D) rate=k[NO] (E) rate=k[NO][O3] (G) rate=k[NO]2[O3]

The rate law is rate = k[NO][O₃]

Option E) is the right answer.

Explanation:

Hi there!

For this generic reaction:

A + B → products

the rate law will be:

rate = k[A]ⁿ[B]ᵃ

this reaction is n-order in A and a-order in B. The overall reaction is the sum of the orders of each reactant, in this case:

Overall order of the reaction = n + a

In our problem, we know that the reaction is first order in O₃ and second order overall. Then:

Overall order of the reaction = Order in NO + Order in O₃

2 = n + 1

2 - 1 = n

n = 1

Then, the reaction is first order in NO and first order in O₃.

The rate law will be:

rate = k[NO][O₃]

The right answer is the option E).