Question

For a mixture of 12.0mL of 0.004. M AgNO3 and 8.0mL of 0.0025 M K2CrO4, a colorimetric measurement of CrO4-2 in the equilibrium supernatant liquid found its concentration to be 1.5*10^-4 M. Calculate the Ksp of Ag2CrO4.

Answer 1

I think the easiest way to handle this is to set up an ICE chart.
Each soln has been diluted so the concns are as followws:
(Ag^+) = 0.004M x (12/20) = 0.0024M
(CrO4^2-) = 0.0025 x (8/20) = 0.0010
.......2Ag^+ + CrO4^2- ==> Ag2CrO4
I...0.0024M....0.0010.......----
C..-0.0020.....-0.0010..........----
E...0.0004......1.5E-4....
Substitute into the Ksp expression and solve for Ksp.