## Relationship between k and k'

$K = \frac{k_{forward}}{k_{reverse}}$

Jason Wu 1E
Posts: 101
Joined: Thu Jul 25, 2019 12:15 am

### Relationship between k and k'

Is there a relationship between k and k'? similar to how Kc of the reverse reaction is Kc^-1?

Myka G 1l
Posts: 100
Joined: Fri Aug 30, 2019 12:17 am

### Re: Relationship between k and k'

K is the normal rate constant for a reaction, let's say for rate = k[A]N[B]M[C]L. However, if [B]0 and [C]0 >> [A]0, we can say that rate = k'[A]N, and that the reaction is a pseudo-first order reaction. Comparing the two, we can see differences in the units of k, with k' having units of L2*mol-2*s-1 and k having units of s-1.

Abigail Sanders 1E
Posts: 112
Joined: Wed Sep 11, 2019 12:16 am

### Re: Relationship between k and k'

Yes so because k is the reaction constant for the forward reaction k' is the reaction constant for the reverse reaction. Thus the equilibrium constant K for the forward direction is equivalent to k/k'. This can be determined because at equilibrium of a+b --> c + d, the rate of the forward reaction (k[a][b]) = the rate of the reverse reaction, k'[c][d] and when these are set equal to one another [c][d]/[a][b] = k/k'= K