Pyrosulfate
In chemistry, disulfate or pyrosulfate is the anion with the molecular formula S
2O2−
7. Disulfate is the IUPAC name. It has a dichromate-like structure and can be visualised as two corner-sharing SO4tetrahedra, with a bridging oxygen atom. In this anion, sulfur has an oxidation state of +6. Disulfate is the conjugate base of the hydrogen disulfate (hydrogen pyrosulfate) ion HS
2O−
7, which in turn is the conjugate base of disulfuric acid (pyrosulfuric acid).
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