AP Chemistry - Solubility Unit Problems Worksheet #1

1. Calculate the Ksp for each of the salts whose solubility is listed below. 

a) CaSO4 = 5.0 x 10-3 mol/L 

b) MgF2 = 2.7 x 10-3 mol/L 

c) AgC2H3O2 = 1.02 g/100 mL 

d) SrF2 = 12.2 mg/100 mL 
 
2. Calculate 

a) the solubility in moles/L of each of three salts and 
b) the concentration of the cations in mg/mL in each of the saturated solutions.

i) AgCN Ksp = 2.0 x 10-12

ii) BaSO4 Ksp = 1.5 x 10-9

iii) FeS Ksp = 3.7 x 10-19

iv) Mg(OH)2 Ksp = 9.0 x 10-12

v) Ag2S Ksp = 1.6 x 10-49

vi) CaF2 Ksp = 4.9 x 10-11
 
3. Consider these slightly soluble salts: 

     i) PbS Ksp = 8.4 x 10-28

    ii) PbSO4 Ksp = 1.8 x 10-8

   iii) Pb(IO3)2 Ksp = 2.6 x 10-13

a) Which is the most soluble? 

b) Calculate the solubility in moles/L for PbSO4

c) How many grams of PbSO4 dissolve in 1 L of solution? 

d) How can you decrease the concentration of Pb2+(aq) in a saturated solution of PbSO4 solution? 

e) What is the concentration in moles/L of PbS in a saturated solution of the salt? 
 
4.  For each of these substances, calculate the milligrams of metallic ion that can remain at equilibrium in a solution having a [OH-] = 1.0 x 10-4 mol/L. 

a) Cu(OH)2 Ksp = 1.6 x 10-9

b) Fe(OH)3 Ksp = 6.0 x 10-38

c) Mg(OH)2 Ksp = 6.0 x 10-12