7. Calculating Solubility Product from Solubility Data

When the solubility S of a slightly soluble salt is experimentally determined, it is possible to calculate the value of K_sp. The solubility equals the amount of salt (in g or in mole) dissolved in 1 L of a saturated solution at the specified temperature.

Let us consider the salt M_pL_q(s) with a solubility of S mol/L:

M_pL_q(s) p M^m+(aq) + q L^n-(aq)

In the saturated solution of M_pL_q:

[M^m+] = p x S and [L^n-] = q x S.

So:

Summary