Dithionic acid

Dithionic acid
Names
	IUPAC name dithionic acid
	Other names hypodisulfuric acid
Identifiers
CAS Number	14970-71-9 ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:29208 ;
ChemSpider	25128 ;
PubChem CID	26985;
UNII	9MP5KH5623 ;
CompTox Dashboard (EPA)	DTXSID50164368 ;
	InChI InChI=1S/H2O6S2/c1-7(2,3)8(4,5)6/h(H,1,2,3)(H,4,5,6) Key: RMGVZKRVHHSUIM-UHFFFAOYSA-N ; InChI=1/H2O6S2/c1-7(2,3)8(4,5)6/h(H,1,2,3)(H,4,5,6) Key: RMGVZKRVHHSUIM-UHFFFAOYAM;
	SMILES O=S(=O)(O)S(=O)(=O)O;
Properties
Chemical formula	H2S2O6
Molar mass	162.14 g mol−1
Acidity (pKa)	−3.4 (estimated)
Conjugate base	Dithionate
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Dithionic acid, H₂S₂O₆, is the inorganic compound with the formula H₂S₂O₆. It is the doubly protonated derivative of dithionate, a well-characterized dianion. Dithionic acid is mainly observed and characterized as an aqueous solution.