H2O2 – hydrogen peroxide – is a clear liquid that is highly soluble in water. In its pure form, H2O2 is very unstable and decomposes easily, often explosively, but is more stable in aqueous solutions. It is used as an oxidizer, bleaching agent, and antiseptic. Weak solutions of H2O2 сan be found in any pharmacy and almost any home. Small wounds and cuts can be treated with hydrogen peroxide. Contact with blood elicits intense foaming, which aids in cleaning a wound. This is facilitated by a special enzyme in the blood known as catalase, and the foaming is caused by oxygen released over the course of the reaction.