Question

A student mixes 5.0 mL of 0.00200 M Fe(NO3)3 with 5.0 mL 0.00200 KSCN. She finds that the
concentration of FeSCN2+ in the equilibrium mixture is 0.000125 M. Follow these steps to
determine the corresponding experimental value of Kc for the reaction of Fe3+ and SCN–
to produce
this complex ion. Show your calculations for each step below and then place the appropriate
value(s) in the equilibrium (or 'ICE') table near the bottom of the page.
Step 1. Calculate the molarity of Fe3+, SCN–
, and FeSCN2+ initially present after mixing the two
solutions, but prior to any reaction taking place. (M1V1 = M2V2)

Answer 1

[Fe(NO3)3] = 0.00200M x (5.0 mL/10.0 mL) = ?
(KSCN) = 0.00200 x (5.0 mL/10.0 mL) = ?
(FeSCN)^2+ = 0

Did you try inserting these numbers into the M1V1 - M2V2 equation the prof gave you in the problem. That will give you the same numbers I have above. Try it.