## Pre-Equilibrium Approach ?

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

Aliya Habib 1L
Posts: 20
Joined: Fri Sep 25, 2015 3:00 am

### Pre-Equilibrium Approach ?

First of all, when would someone use this.
Secondly, When you get an expression such as $K=\frac{2k_{1}k_{2}}{k_{1}}$ how many values would we be given usually to solve for K ?

Emi Nakahara 3F
Posts: 21
Joined: Wed Sep 21, 2016 2:57 pm

### Re: Pre-Equilibrium Approach ?

It can be used to determine which step in a reaction process is the rate-limiting step. By taking each step of a reaction, we write the rate law for it like k[R][R2] and substitute the intermediates, and then see if it matches the overall reaction rate. An example of this can be seen in the winter 2016 final question 4B.

You don't really need to solve for the value of K, unless k1, k1, and k inverse are all given, but I haven't really seen a problem with those yet..? Hope this helped.