The elementary steps for the gas-phase reaction 2 NO(g) + Br₂(g) → 2 NOBr(g) are proposed to be
(1) NO(g) + Br₂(g) ⇌ NOBr₂(g) (fast)
(2) NOBr₂(g) + NO(g) → 2 NOBr(g) (slow)
Which of the following rate laws is most consistent with this mechanism?
a) rate = k[NO][Br₂]
b) rate = k[NO]²[Br₂]
c) rate = k[NOBr₂][NO]
d) rate = k[NO]²[Br₂]²