Solubility of Ag2CrO4 in water is 2.7x10^-3g/100.mL. Estimate Ksp of Ag2CrO4 at that temperature.?

Question

Solubility of Ag2CrO4 in water is 2.7x10^-3g/100.mL. Estimate Ksp of Ag2CrO4 at that temperature.?

Answer 1

Ksp is given in terms of molarities. The molecular weight of Ag2CrO4 is 331.7 g/mol, so the molarity of the saturated solution is:

(2.7x10^-3 g) / (0.1 L) (331.7 g/mol) = 8.14x10^-6 mol/L.

Since Ag2CrO4 (s) ↔ 2 Ag+ (aq) + CrO4-- (aq)

Ksp = [Ag+]² [CrO4--]

Let x = molar solubility

Ksp = [2x]² [x] = 4x³

Substituting,

Ksp = (4) (8.14x10^-6)³ = 2.16x10^-15.