Chlorosulfuric acid

Chlorosulfuric acid
Names
	IUPAC name Sulfurochloridic acid
	Other names Chlorosulfuric acid,; Chlorosulfonic acid,; Chlorosulphonic acid,; Chlorinesulfonic acid,; Chlorinesulphonic acid,; Chloridosulfonic acid,; Chloridosulphonic acid,; Sulfuric chlorohydrin
Identifiers
CAS Number	7790-94-5 ;
3D model (JSmol)	Interactive image;
ChemSpider	23040 ;
ECHA InfoCard	100.029.304
EC Number	232-234-6;
PubChem CID	24638;
RTECS number	FX5730000;
UNII	2O9AXL1TJ4 ;
UN number	1754
CompTox Dashboard (EPA)	DTXSID1029706 ;
	InChI InChI=1S/ClHO3S/c1-5(2,3)4/h(H,2,3,4) Key: XTHPWXDJESJLNJ-UHFFFAOYSA-N ; InChI=1/ClHO3S/c1-5(2,3)4/h(H,2,3,4) Key: XTHPWXDJESJLNJ-UHFFFAOYAO;
	SMILES ClS(=O)(=O)O;
Properties
Chemical formula	HSO3Cl
Molar mass	116.52 g mol−1
Appearance	colorless liquid, but commercial samples usually are pale brown
Density	1.753 g cm−3
Melting point	−80 °C (−112 °F; 193 K)
Boiling point	151 to 152 °C (304 to 306 °F; 424 to 425 K) (755 mmHg or 100.7 kPa)
Solubility in water	hydrolysis
Solubility in other solvents	reacts with alcohols; soluble in chlorocarbons
Acidity (pKa)	−5.9 (in CF3CO2H)
Refractive index (nD)	1.433
Structure
Molecular shape	tetrahedral
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H314, H335
Precautionary statements	P260, P261, P264, P271, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P321, P363, P403+P233, P405, P501
NFPA 704 (fire diamond)	3 0 2 W; OX
Safety data sheet (SDS)	ICSC 1039
Related compounds
Related compounds	Sulfuryl chloride; Sulfuric acid
	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

Chlorosulfuric acid (IUPAC name: sulfurochloridic acid) is the inorganic compound with the formula HSO₃Cl. It is also known as chlorosulfonic acid, being the sulfonic acid of chlorine. It is a distillable, colorless liquid which is hygroscopic and a powerful lachrymator. Commercial samples usually are pale brown or straw colored.

Salts and esters of chlorosulfuric acid are known as chlorosulfates.