Question

How do you calculate Ksp from solubility?

Answer 1

Well, let us seek an example....

Explanation:

For `"lead(II) chloride"`, this site quotes a solubility of `10.8*g*L^-1` under standard condition..., and this is a molar solubility of `((10.8*g)/(278.10*g*mol^-1))/(1*L)=0.03883*mol*L^-1` so we address the equilibrium....

`PbCl_2(s) stackrel(H_2O)rightleftharpoonsPb^(2+) + 2Cl^-`

And in the standard way, we write the `"solubility expression..."`, with `S="molar solubility of lead chloride"`

`K_"sp"=[Pb^(2_+)][Cl^-]^2=Sxx(2S)^2=4xx(0.03833)^3=2.28xx10^-4` ...