Question

A generic salt, ab2, has a molar mass of 169 g/mol and a solubility of 1.10 g/l at 25 °c. what is the ksp of this salt at 25 °c?

Answer 1

AB₂(s) ⇄ A²⁺(aq) + 2B⁻(aq)

Ksp=[A²⁺][B⁻]²

a=1.10 g/L
M=169 g/mol

c=a/M

[A²⁺]=c=a/M
[B⁻]=2c=2a/M

Ksp=(a/M)(2a/M)²=4(a/M)³

Ksp=4*(1.10/169)³=1.103×10⁻⁶