Calculate the solubility (in g/L) of CaSO4(s) in 0.400 M Na2SO4(aq) at 25°C . The 𝐾sp of CaSO4 is 4.93×10−5 . solubility: g/L

Answer 1

CaSO₄(s) ==> Ca²⁺(aq) + SO₄^2-(aq)

Ksp = [Ca²⁺][SO₄^2-]

The common ion is SO₄^2-

[SO₄^2-] = 0.400 M

Ksp = 4.93x10^-5 = [Ca²⁺][0.400]

[Ca²⁺] = 1.23x10^-4 M

molar mass CaSO₄ = 136 g / mol

1.23x10^-4 mol/L x 136 g / mol = 0.0168 g / L