Suppose the reaction between nitric oxide and bromine proceeds by the following mechanism: step elementary reaction rate constant (g) (g) (g) (g) (g) (g) Suppose also ≫. That is, the first step is much faster than the second.

Write the balanced chemical equation for the overall chemical reaction:

Write the experimentally-observable rate law for the overall chemical reaction.

Note: your answer should not contain the concentrations of any intermediates.

Koverall [NO]^2 [Br2]

Balanced chemical reaction equation;

2NO + Br2 ⇄2NOBr

Explanation:

Consider the first step in the reaction;

NO (g) + Br2 (g) ⇄ NOBr2 (g) fast

The second step is the slower rate determining step

NOBr2 (g) + NO (g) ⇄ 2NOBr (g)

Given that k1 = [NOBr2]/[NO] [Br2]

k2 = [NOBr2] [NO]

The concentration of the intermediate is now;

[NOBr2] = k1[NO][Br2]

It then follows that overall rate of reaction is

Rate = k1k2[NO]^2 [Br2]

Since k1k2=Koverall

Rate = Koverall [NO]^2 [Br2]