Chapter 14.5, Problem 4CP

A plausible mechanism for the reaction:

$\begin{array}{l}{\text{H}}_{\text{2}}\text{+ 2IBr}\underset{}{\to }{\text{ I}}_{\text{2}}\text{+ 2HBr}\hfill \\ \text{is the following:}\hfill \\ {\text{Step I: H}}_{\text{2}}\text{+ IBr}\stackrel{k_1}{\to }\text{ HI + HBr }\left(\text{slow}\right)\hfill \\ \text{Step 2: HI + IBr}\stackrel{}{\to }{\text{ I}}_{\text{2}}\text{+ HBr }\left(\text{fast}\right)\hfill \\ \text{Select the rate law that will be determined experimentally}\text{.}\hfill \\ \text{a)}\hfill \\ \text{rate = }k{\left[\text{H}\right]}^{\text{2}}\hfill \\ \text{b)}\hfill \\ \text{rate = }k{\text{[H}}_{\text{2}}{\text{][IBr]}}^{\text{2}}\hfill \\ \text{c)}\hfill \\ \text{rate = }k{\text{[IBr]}}^{\text{2}}\hfill \\ \text{d)}\hfill \\ \text{rate = }k{\text{[H}}_{\text{2}}\text{]}\left[\text{IBr}\right]\hfill \\ \text{e)}\hfill \\ \text{rate = }k\left[\text{HI}\right]\left[\text{IBr}\right]\hfill \end{array}$