A student mixes 5.0 mL 2.00 x 10-3 M Fe(NO3)3 with 5.0 mL 2.00 x l0-3 M KSCN. She finds that in the equilibrium mixture the concentration of FeSCN2+ is 1.2 x l0-4 M. Find Kc for the reaction
Fe3+ (aq) + SCN-(aq) ↔ FeSCN2+(aq).
Step 1 Find the number of moles Fe3+ and SCN- initially present.