Solubility Product K_sp

Definition: The product of the concentrations of cation and anion in a saturated solution of a salt is called solubility product. Higher the K_sp value, solubility of the salt is more.

K_sp = [A⁺][B^-] - if it is saturated solution

K_sp > [A⁺][B^-] - if it is unsaturated solution

K_sp < [A⁺][B^-] - if it is super saturated solution

Example:
Solubility product of AgCl is:

K_sp = [Ag⁺][Cl^-]

Sample Calculations:

Calculate the value of Solubility Product K_sp if t solubility of AgCl in pure water is 1.3 x 10^-5 M.

K_sp = [Ag⁺][Cl^-] = [1.3 x 10^-5 M][1.3 x 10^-5 M] = 1.69 x 10^-10