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.
