Polythionic acid

Polythionic acid is an oxoacid which has a straight chain of sulfur atoms and has the chemical formula Sn(SO3H)2 (n + 2 > 2).

Names of polythionic acids are determined by the number of atoms in the chain of sulfur atoms: Numerous acids and salts of this group have a venerable history, and chemistry systems, where they exist, dates back to the studies John Dalton devoted to the behavior of hydrogen sulfide in aqueous solutions of sulfur dioxide (1808).

This solution now has the name of Heinrich Wilhelm Ferdinand Wackenroder, who conducted a systematic study (1846).

Over the next 60–80 years, numerous studies have shown the presence of ions, in particular tetrathionate and pentathionate anion (S4O2−6 and S5O2−6, respectively).

Many methods exist for the synthesis of these acids, but the mechanism is unclear because of the large number of simultaneously occurring and competing reactions such as redox, chain transfer, and disproportionation.