Sodium peroxoborate has the empirical formula "NaBO 3.xH 2O". World annual production in 1995 was approximately 750,000 tonnes, and its use in washing powders dates back to 1907 with Henkel's original "Persil" product in Germany. It is cheap and readily available, being produced mainly as a solid ingredient of domestic washing formulations, in which it acts as sources of H 2O 2 in solution for stain bleaching. Sodium peroxoborate is a solid peroxygen compound with exceptional storage stability and no shock sensitivity. In 1934, the English mathematical physicist William Penney and the Scottish physicist Gordon Sutherland proposed a molecular structure for hydrogen peroxide which was very similar to the presently accepted one and which subsequent evidence cumulatively proved to be correct. At least half a dozen hypothetical molecular structures seemed to be consistent with the available evidence. In 1892 the Italian physical chemist Giacomo Carrara (1864-1925) determined its molecular weight by freezing point depression, which confirmed that its molecular formula was H 2O 2. Pure hydrogen peroxide was first obtained in 1894 - almost 80 years after its discovery - by Richard Wolffenstein, who produced it via vacuum distillation.ĭetermination of the molecular structure of hydrogen peroxide proved to be very difficult. This instability was due to traces of impurities (transition metals salts) which catalyze the decomposition of the hydrogen peroxide. Pure hydrogen peroxide was long believed to be unstable as early attempts to separate it from the water, which is present during synthesis, all failed. Thénard's process was used from the end of the 19th century until the middle of the 20th century. An improved version of this process used hydrochloric acid, followed by addition of sulfuric acid to precipitate the barium sulfate byproduct. Hydrogen peroxide was first described in 1818 by Louis Jacques Thénard, who produced it by treating barium peroxide with nitric acid. Hydrogen peroxide can be used for tooth whitening and when mixed with baking soda and salt forms a recipe for home-made toothpaste. The chemical's bleaching property lends its name to the phrase "Hollywood peroxide blonde". Diluted H 2O 2 (between 1.9% and 12%) mixed with ammonium hydroxide has been used to bleach human hair. Concentrated H 2O 2, or 'high-test peroxide' is a reactive oxygen species and has been used as a propellant in rocketry.
For laboratory use, 100 volume, 30 wt% solutions are the most common. The concentrations are sometimes described in terms of the volume of oxygen gas generated one milliliter of a 20-volume solution generates twenty milliliters of oxygen gas when completely decomposed. For consumers, it is usually available from pharmacies at 3 and 6 wt% concentrations. For safety reasons it is normally used as an aqueous solution, also colourless. It is a strong oxidizer and is used as a bleaching agent and disinfectant. Hydrogen peroxide (H 2O 2) is the simplest peroxide (a compound with an oxygen-oxygen single bond) and in its pure form is a colourless liquid that is slightly more viscous than water. Metal oxides, peroxides and superoxides.Preparation via the anthraquinone process.
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