8. Calculating Solubility from Solubility Product

For any ionic compound with general formula M_pL_q , solubility product K_sp and solubility S (mol/L) we have:

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

For every M_pL_q-particle going into solution, p M^m+-ions and q L^n--ions are formed.

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

When we combine this with the expression for K_sp:

we find:

Summary