The Ksp for silver chromate (Ag2CrO4) is 1.1x10-12. Using the same initial set up of 10mL of 1M silver nitrate is combined with 25mL of 0.1M sodium chromate, what is the reaction quotient (Q) of the silver chromate? (Is a precipitate going to form?)

Answer 1

Ag2CrO4 ==> 2Ag^+ + CrO4^2-
Qsp = (Ag+)^2(CrO4^2-) = ?
(Ag^+) = 1 M x (10 mL/35 mL) = 0.286 M
(CrO4^2-) = 0.1 M x (25 mL/35 mL) = 0.0714 M
Plug into the above to find Qsp. If Qsp > Ksp you get a ppt.