Determination of the Equilibrium Constant How to determine E

Determination of the Equilibrium Constant

How to determine Equil [FeNCS2+] M , Equil. [Fe3+] M & Equil. [SCN-] M given

initial [Fe3+] M of 1.00x10-3

and initial [SCN-] M of 2.00x10-4

I am not given a Keq value..that has to be figured out..how would make use of an ICE chart?

Solution

First, write the balanced chemical equation with an ICE table.

Fe³⁺    +    SCN^- FeSCN²⁺
IC:    1.0 x 10^-3 2.0 x 10^-4    0
C: -x -x    +x
EC:    1.0 x 10^-3 x 2.0×10^-4 x    x

Now,

Equilibirium constant, K = [FeSCN²⁺]_eq / { [Fe³⁺]_eq [SCN^-]_eq }

So, you need the value of K, to find the value of x.