What is "tetrathionate"

Tetrathionate \Tet`ra*thi"on*ate\, n. (Chem.) A salt of tetrathionic acid.

n. (context inorganic chemistry English) The oxyanion S₄O₆^2- derived from tetrathionic acid; any salt containing this ion

The tetrathionate anion, , is a sulfur oxoanion derived from the compound tetrathionic acid, HSO. Two of the sulfur atoms present in the ion are in oxidation state 0 and two are in oxidation state +5. Alternatively, the compound can be viewed as the adduct resulting from the binding of to SO. Tetrathionate is one of the polythionates, a family of anions with the formula [S(SO)]. Its IUPAC name is (sulfonatodisulfanyl)sulfonate, the name of its corresponding acid is (sulfodisulfanyl)sulfonic acid. The Chemical Abstracts Service identifies tetrathionate by the CAS Number 15536-54-6.