To calculate the solubility product, first write a solubility product expression. Then, substitute the equilibrium concentrations of dissolved solute ions into the expression, and expand and simplify to find a numerical value. To finish, work out the units of the solubility product by substituting the units of your equilibrium concentrations into the solubility product expression, expanding and simplifying once again. We cover plenty of examples of solubility product calculations in this article.