Chemical database: 4. Hydrogen peroxide

Hydrogen peroxide (H2O2) is a colorless, relatively unstable liquid which slowly decomposes to water (H2O) and oxygen (O2). It can be mixed with water in any ratio. On the market, one can mostly found it as a 3% or a 30% solution. Density = 1.4 g/cm3. Melting point = -11°C. Boiling point = 150.2°C. H2O2 is mostly stored in dark brown glass bottles, sometimes with H3PO4 added, to slow down decomposition. Because of its intensive oxidative properties, it is often used for whitening (mostly of paper, but it is used in some hair whitening products as well). It is also used for desinfection, in hobby rocketry (where it can be used alone, or in combination with various fuels), in chemical industry for the manufacture of various substances, etc. One should be careful with higher concentrations, because it can easily burn and even whiten one's skin.

Hydrogen peroxide can be found in usual stores, in form of hair whitening products. Unfortunately, in that form it mostly can't be used because of many additional substances that are usually added to this kind of products. Pure 30% solution, in quantity of 1000 ml, can be ordered from drugstores/pharmacies, and every larger drugstore should sell solutions of various concentrations (3%, 6%, 9%, 12%) in quantities of 100 ml. The price can range from 1.5 to 3€ (in the Croatian market).