The following reaction mechanism has been proposed for the reaction of $\ce{NO}$ with $\ce{Br2}$ to form $\ce{NOBr}$
$$\begin{align} \ce{NO(g) + Br2(g)&<=>NOBr2(g)}\\ \ce{NOBr2(g) + NO(g) &-> 2NOBr(g)} \end{align}$$ If the second step is the rate determining step, what is the order of the reaction with respect to $\ce{NO}$?
Since the 2nd step is the rate determining, shouldn't the order with respect to $\ce{NO}$ be 1? According to my book though, the correct answer is 2. What am I missing here?