Hydrogen peroxide is a chemical compound and is pale blue liquid in its pure form which appears colourless in a dilute solution. It’s a clear liquid, slightly more viscous than water. Hydrogen peroxide is weak acid and has strong oxidizing properties. It is the simplest peroxide (a compound with an oxygen–oxygen single bond). It can be used as an bleaching agent, oxidizer and antiseptic. Concentrated hydrogen peroxide, or “high-test peroxide”, is a reactive oxygen species and has been used as a propellant in rocketry. Its chemistry is dominated by the nature of its unstable peroxide bond.