Tetrathionic

Tetrathionic is a chemical compound with the formula H2S4O6. It is an oxyacid of sulfur, meaning it contains hydrogen, sulfur, and oxygen atoms. Tetrathionic acid itself is unstable and typically exists only in aqueous solution. It is a member of the polythionic acid series, which are characterized by chains of sulfur atoms.

The most common form in which tetrathionate is encountered is as a salt, such as sodium tetrathionate (Na2S4O6). Tetrathionate ions are formed during the oxidation of thiosulfate, often in the presence of iodine. This reaction is sometimes used as a titration method to determine the concentration of thiosulfate. The oxidation of sulfide minerals can also lead to the formation of tetrathionate.

Tetrathionic acid is a relatively weak acid. Its salts are generally soluble in water. The tetrathionate ion has a specific structure with four sulfur atoms linked in a chain, with two oxygen atoms attached to the terminal sulfur atoms and a negative charge distributed across the molecule. In solution, tetrathionate can undergo hydrolysis, particularly under acidic or basic conditions, breaking down into other sulfur species. The study of polythionic acids, including tetrathionic acid, is important in understanding sulfur chemistry in various natural and industrial processes.