The reaction, X + 2Y + Z → N occurs by the following mechanism (i) X + Y leftharpoons M (very rapid equilibrium) (ii) M + Z → O (slow) (iii) O + Y → N (very fast) What is the rate law for this reaction?

Question

The reaction, X + 2Y + Z → N occurs by the following mechanism (i) X + Y leftharpoons M (very rapid equilibrium) (ii) M + Z → O (slow) (iii) O + Y → N (very fast) What is the rate law for this reaction? (A) Rate = k[Z] (B) Rate = k[X][Y]2[Z] (C) Rate = k[N] (D) Rate = k[X][Y][Z]

Tardigrade Admin · Accepted Answer

KC =([M]/[X][Y]) ⇒ [M] = KC [X][Y] Rate = K'[M][Z] =K' Kc [X][Y][Z] = K[X][Y][Z]

Q. The reaction, $X + 2 Y + Z \to N$ occurs by the following mechanism
(i) $X + Y ⇌ M$ (very rapid equilibrium)
(ii) $M + Z \to O$ (slow)
(iii) $O + Y \to N$ (very fast)
What is the rate law for this reaction?

Rate $= k [Z]$

Rate $= k [X] [Y]^{2} [Z]$

Rate $= k [N]$

Rate $= k [X] [Y] [Z]$

$K_{C} = \frac{[ M ]}{[ X ] [ Y ]} \Rightarrow [M] = K_{C} [X] [Y]$
Rate $= K^{'} [M] [Z] = K^{'} K_{c} [X] [Y] [Z]$
$= K [X] [Y] [Z]$

Q. The reaction, X+2Y+Z→N occurs by the following mechanism (i) X+Y⇌M (very rapid equilibrium) (ii) M+Z→O (slow) (iii) O+Y→N (very fast) What is the rate law for this reaction?

Rate =k[Z]

Rate =k[X][Y]2[Z]

Rate =k[N]

Rate =k[X][Y][Z]