Peroxydisulfuric acid
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Names | |
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IUPAC names
μ-peroxido-bis(hydroxidodioxidosulfur)
peroxydisulfuric acid | |
Other names
Persulfuric acid, Peroxodisulfuric acid
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Identifiers | |
3D model (JSmol)
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ChEBI | |
ChemSpider | |
PubChem CID
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
H2O8S2 | |
Molar mass | 194.13 g·mol−1 |
Appearance | Colourless solid |
Melting point | 65 °C (149 °F; 338 K) (decomposes) |
soluble | |
Conjugate base | Peroxydisulfate |
Related compounds | |
Other cations
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Potassium persulfate Sodium persulfate Ammonium persulfate |
Related compounds
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Peroxymonosulfuric acid Pyrosulfuric acid |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
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Infobox references | |
Peroxydisulfuric acid is an inorganic compound with a chemical formula H2S2O8. Also called Marshall's acid after its inventor Professor Hugh Marshall,[1] it is a sulfur oxoacid.[2] In structural terms it can be written HO3SOOSO3H. It contains sulfur in its +6 oxidation state and a peroxide group. Its salts, commonly known as persulfates, are industrially important as powerful oxidizing agents.
Synthesis[]
The acid is prepared by the reaction of chlorosulfuric acid with hydrogen peroxide:[3]
- 2ClSO3H + H2O2 → H2S2O8 + 2 HCl
Another method is the electrolysis of moderately concentrated sulfuric acid (60-70%) with platinum electrodes at high current density and voltage:
- H2SO4 + H2O → H3O+ + HSO4− (dissociation of sulfuric acid)
- 2HSO4− → H2S2O8 + 2e− (E0 = +2.4V) (bisulfate oxidation)
- 2H2SO4 → H2S2O8 + H2 (overall reaction)
- 3H2O → O3 + 6H+ (ozone produced as a side product)
See also[]
- Peroxymonosulfuric acid (Caro's acid)
- Piranha solution
References[]
- ^ Senning, Alexander (2006-10-30). Elsevier's Dictionary of Chemoetymology: The Whys and Whences of Chemical Nomenclature and Terminology. ISBN 9780080488813.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
- ^ Harald Jakob, Stefan Leininger, Thomas Lehmann, Sylvia Jacobi, Sven Gutewort. "Peroxo Compounds, Inorganic". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a19_177.pub2.CS1 maint: multiple names: authors list (link)
Categories:
- Hydrogen compounds
- Peroxy acids
- Persulfates
- Sulfur oxoacids
- Inorganic compound stubs