Which salts will be more soluble in an acidic solution than in pure water?

The solubility of any substance whose anion is basic will be affected to some extent by the pH of the solution. For example, consider Mg (OH) 2, A saturated solution of Mg (OH) 2 has a calculated pH of 10.52 and contains [Mg2+] = 1.7 10-4 M. The solubility of almost any ionic compound is affected if the solution is made sufficiently acidic or basic. The effects are very noticeable, however, only when one or both ions involved are at least moderately acidic or basic. The metal hydroxides, such as Mg (OH) 2, are examples of compounds containing a strongly basic ion, the hydroxide ion.