Question

LAB INFORMATION:

Initial

Fe3+ =2.00 x 10-3 M

SCN- = 2.00 x 10-3 M

FeSCN3+ = 1.50 x 10-4 M

MIXTURE	ABSORBANCE	FeSCN2+
1	0.149	3.08 x 10^-5
2	.250	5.17 x 10^-5
3	0.314	6.49 x 10^-5
4	0.437	9.03 x 10^-5
5	0.521	1.08 x 10^-5

I am supposed to complete a table for each of them; table looks like this for all five of the mixtures:

Mixture ##	[Fe^3+]	[SCN^-1]	[FeSCN^2+]
Initial
Change
Equilibrium

Kc=

But I'm not sure how to get started; the data that we used was:

	1	2	3	4	5
Volume Fe(NO3)3	5.00	5.00	5.00	5.00	5.00
Volume KSCN solution (mL)	1.00	2.00	3.00	4.00	5.00
Volume H2O (mL)	4.00	3.00	2.00	1.00	0

all of them are to equal 10mL (all mixtures)

I think this is all the information that is needed; Its fine if I only get shown at least like 2, I just want to make sure I understand it

Answer 1

Corrections- In 5th line it will be FeSCN2+ instead of FeSCN3+

From given data it is clear that we don't have any FeSCN2+ ions in our initial solution because we are adding only Fe(NO3)3 and KSCN. So the initial concentration of FeSCN2+ should be zero but it is given  1.50 x 10-4 M. I don't know how.  

Well, I will solve this question for both cases if initial concentration is zero or if initial concentration is anyhow non zero. ( but the second case of non zero concentration is not logical. Please check it out again)

Case -1

change in concentration = (equilibrium - initial)concentration similar calculations for all other mixtures can be done.

Case - 2