What general condition must be met for the pH of a solution to significantly alter a salt's solubility?

Answer

At least one ion produced upon dissolution must be capable of acting as an acid or base in water.

The influence of pH is rooted in acid-base reactions that couple with the dissolution equilibrium. If neither the cation nor the anion reacts significantly with excess $ ext{H}^+$ or $ ext{OH}^-$ ions, the solubility remains independent of the solution's pH.

What general condition must be met for the pH of a solution to significantly alter a salt's solubility?
ChemistryacidBasepHsolubility