How are peroxy acids commonly prepared from oxyacids?

Peroxy acids are typically prepared by reacting an oxyacid with hydrogen peroxide.1

In this process, the atomic group —O—O—H replaces the —O—H group of the oxyacid. Because some oxyacids are weak, small amounts of strong acids, such as sulfuric acid, are often added to the mixture to accelerate the reaction.1