Solubility Products, Ksp, of Salts

The solubility product Ksp for a salt is the product of the ion concentrations of the salt. For example, the ionization of the salt Li2CO3 in a solution is,

Li2CO3 = 2 Li+ + CO32- . . . Ksp = [Li+]2 [CO32-]

In the following table, the salts are grouped by the anions: carbonates, chromates, halides, hydroxides, oxalate, sulfates, and sulfides.

Substance T
°C
Ksp
Carbonates
CaCO3 25 5 × 10-9
PbCO3 20 1.4 × 10-13
Li2CO3 0 2 × 10-3
NiCO3 25 1.2 × 10-7
Chromates
PbCrO4 25 1.8× 10-14
Ag2CrO4 25 1.1× 10-12
SrCrO4 25 3.5× 10-5
Halides: chlorides,
bromides, iodides
CuI 18 7 × 10-13
PbBr2 20 9 × 10-6
PbCl2 20 1.2 × 10-5
HgI2 25 3 × 10-29
Hg2Br2 25 6 × 10-23
Hg2Cl2 25 1.4 × 10-18
AgBr 100 5 × 10-10
AgCl 10 4 × 10-11
AgI 25 9 × 10-17
Hydroxides
Ca(OH)2 0 9 × 10-6
Fe(OH)2 18 7 × 10-16
Pb(OH)2 20 2 × 10-15
Mn(OH)2 18 1.7 × 10-13
Oxalates
CdC2O4 25 1.5× 10-8
MgC2O4 25 8.5× 10-5
Sulfates
BaSO4 25 1.1 × 10-10
CaSO4 30 6 × 10-5
Hg2SO4 25 7 × 10-7
Ag2SO4 0 5 × 10-6
SrSO4 0 4 × 10-7
Sulfides
CdS 18 4 × 10-30
MnS 18 3 × 10-14
HgS 18 1.5 × 10-53
CuS 18 2 × 10-37