Steve Marsden’s

In the lab we saw that although salts are the products of "neutralization" reactions, water solutions of salts are not necessarily "neutral", i.e., pH 7. Hydrolysis is the reaction of an ion with water, usually to produce a solution that is acidic or basic.

Examining the observations from the experiment it should be possible to generalize a simple rule for predicting whether a salt solution will in fact be neutral or whether it will be acidic or basic.

Why does this "rule" work?

There are at least two approaches to explaining hydrolysis, one relying on LeChâtelier's Principle, and one using the conventions of the Brønsted model.