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pyrosulfate

alt. (context inorganic compound English) Any salt of pyrosulfuric acid. n. (context inorganic compound English) Any salt of pyrosulfuric acid.

Wikipedia
Pyrosulfate

In chemistry, disulfate or pyrosulfate is the anion with the molecular formula . Disulfate is the IUPAC name. It has a dichromate-like structure and can be visualised as two corner-sharing SO tetrahedra, 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 , which in turn is the conjugate base of disulfuric acid (pyrosulfuric acid).