Peroxodisulfuric acid
Structural formula | ||||||||||
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General | ||||||||||
Surname | Peroxodisulfuric acid | |||||||||
other names |
Marshallic acid |
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Molecular formula | H 2 S 2 O 8 | |||||||||
Brief description |
white, inconsistent crystals |
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properties | ||||||||||
Molar mass | 194.15 g mol −1 | |||||||||
Physical state |
firmly |
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Melting point |
60 ° C |
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safety instructions | ||||||||||
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Peroxodisulfuric acid is an oxo acid of sulfur (Marshall's acid). It forms white crystals that are soluble in water. Peroxodisulfuric acid has a strong oxidizing effect. It is used, for example, for the production of hydrogen peroxide (via hydrolysis ), for hydroxylation of phenols and as a pickling solution for the surface treatment of metals . Its salts, the peroxodisulphates , are much more stable than the acid and are used as strong oxidizing agents.
![](https://upload.wikimedia.org/wikipedia/commons/thumb/8/87/Peroxydisulfuric-acid-3D-balls.png/220px-Peroxydisulfuric-acid-3D-balls.png)
synthesis
The production of peroxodisulfuric acid in solution takes place technically via electrolysis of an approx. 50% sulfuric acid solution at a high current density . In the laboratory, the same reaction that leads to peroxomonosulfuric acid with an excess of chlorosulfonic acid is used for pure preparation .
Individual evidence
- ↑ a b c Entry on peroxodisulfuric acid. In: Römpp Online . Georg Thieme Verlag, accessed on June 13, 2014.
- ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
- ↑ G. Brauer (Ed.): Handbook of Preparative Inorganic Chemistry 2nd ed., Vol. 1, Academic Press 1963, pp. 389-390.