Trine University Solubility Constant Expression Chemistry Problems

1. Write the solubiltiy constant expression (Ksp = [prod]/[react]) for the following substances:
a. Al(OH)3 b. Ba3(AsO4)2 c. CaF2 d. Hg2Cl2

2. Calculate the solubility product for the following:
a. 0.005 M CaSO4 b. 0.125 M Ag2CO3 c. 0.0450 M Cr(OH)3

3. Calculate the molar solubility (ie. the concentration of a saturated solution) for the following:
a. CaSO4 (Ksp = 2.4 x 10-5
) b. Ag2CO3 (Ksp =8.1 x 10-12) c. Cr(OH)3 (Ksp = 1.6 x 10-30)

4. This is a common ion problem. The Ksp for Ba(IO3)2 is 1.5 x 10-9
. Calculate, the following:
(hint: think Le Chatlier’s principle, if there is something is present how will it shift the equilibrium)
a. The molar solubility
b. the molar solubility of Ba(IO3)2 in a 0.010 M Ba(NO3)2 solution
c. the molar solubility of Ba(IO3)2 in a 0.010 M NaIO3 solution

5. For the solubility of a molecule A2B explain how the concentrations of the species A+ and B2- dictate if
a precipitate will form or not. Formulate your answer using the idea of the reaction quotient (Q) and
Le Chatlier’s principle. (hint: What must be true about the concentrations of these two species with
regard to the Ksp for a precipitate to form or not form.)

6. Calcium fluoride, CaF2, has a Ksp of 4.0 x 10 -11. Predict whether or not a precipitate will form when
100 mL of 2.0 x 10 -4 M Ca2+ and 100 mL of 2.0 x 10 -4 M F-
solutions are mixed. Note – You must
account for the dilution of each species when they are mixed.

7. A solution is 0.10 M in Ca2 and 0.050 M in Sr2
. You want to quantitatively separate the two metals
via precipitation with carbonate ion (CO3
2-
). Can this be accomplished? (CaCO3 Ksp = 4.5 x 10-9 ;
SrCO3 Ksp = 9.3 x 10-10)