Question

Consider the following reaction: 2 C + D → J + 2 K You are told that the rate of this reaction is second order overall and second order in [C]. Could any of the following be a rate-determining first step in a reaction mechanism that is consistent with the observed rate law for the reaction (note that substance Z is an intermediate)?

Answer 1

This is an incomplete question. The complete question is:

Consider the following reaction: 2 C + D → J + 2 K .You are told that the rate of this reaction is second order overall and second order in [C]. Could any of the following be a rate-determining first step in a reaction mechanism that is consistent with the observed rate law for the reaction (note that substance Z is an intermediate)?

Answer choices

C → J + Z

C + C → K + Z

D → J + K

C + D → J + Z

Answer:

C + C → K + Z

Explanation:

Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

$2C+D\rightarrow J+2K$

$Rate=[C]^x[D]^y$

given x = 2

Over all order = x+ y = 2

Thus y= 0

$Rate=[C]^2[D]^0$

Thus the rate determining step must use two molecules of C as that determines the order of reaction.

The only choice that fits in is C + C → K + Z