Open book structure of hydrogen peroxide
Hydrogen peroxide (H2O2) is the simplest peroxide (a compound with an oxygen–oxygen single bond) and an oxidizer.
It is a colorless liquid at room temperature which is slightly viscous than water, with a bitter taste. Traces of gaseous hydrogen peroxide occur naturally in the air. Small amounts of H2O2 is also found in water and some fruit's.
Hydrogen peroxide is non–linear, non–planar molecule with a open book structure. The –O–O– linkage is called peroxy linkage. Hydrogen peroxide is unstable, decomposes readily into oxygen and water, hence it acts as a good oxidizing agent. It is often used as a bleach and cleaning agent.
Manufacture of Hydrogen peroxide by Electrolysis
In laboratory, hydrogen peroxide may be prepared from sodium peroxide or barium peroxide. Hydrogen peroxide can be prepared on a large scale by the electrolysis of ammonium hydrogen sulphate dissolved in excess of sulfuric acid using platinum electrodes and a high current density. In this process, ammonium per–sulphate is produced by oxidation at the anode while hydrogen is liberated at the cathode.
A Hydrogen peroxide plant with Anthraquinone process
The most important manufacturing process for high yield of hydrogen peroxide involves the oxidation of 2–alkylanthraquinone in presence of oxygen produces hydrogen peroxide and the original anthraquinone.
Hydrogen peroxide has an interesting chemistry because of its ability to function as an oxidant as well as a reductant in both acid and alkaline solutions. The oxidation state of oxygen in hydrogen peroxide is –1. It can, therefore, be oxidized to O2 (zero oxidation state) or reduced to H2O or OH (– 2 oxidation state for oxygen). On the whole, hydrogen peroxide is a very powerful oxidizing agent and a poor reducing agent.
Hydrogen peroxides can cause spontaneous combustion on reaction with organic compounds due to its oxidizing property.
Hydrogen peroxide used in mouth washes
Applications:
- In the production of organic compounds such as epoxides, propylene oxide and polyurethanes.
- Act as an aerating agent in production of sponge rubber.
- Used as components in rocket fuels.
- At low concentrations hydrogen peroxides are used for medicinal applications, in pharmaceuticals,cosmetics and as bleach for cloths.
- Hydrogen peroxide are used as germicidal agents for washing wounds, teeth and ears,these are considered to be the safest disinfectants.
- It is used in treatment of waste water.
- High concentrations of it, are used as bleach in paper and textile industries.