Chapter 20, Problem 70E

A simplified rate law 1o the reaction ${\text{2O}}_{\text{2}}\left(\text{g}\right)\to 3{\text{O}}_{\text{2}}\left(\text{g}\right)$ is
$\text{rate=k}\frac{{\left[{\text{O}}_3\right]}^2}{\left[{\text{O}}_{\text{2}}\right]}$

For this reaction, propose a two-step mechanism that consists of a fast, reversible first step, followed by a slow second step.