Nitrosylsulfuric acid

Nitrosylsulfuric acid
Names
	IUPAC name Nitrosylsulfuric acid
	Other names nitrosonium bisulfate, chamber crystals
Identifiers
CAS Number	7782-78-7 ;
3D model (JSmol)	Interactive image;
ChemSpider	74147 ;
ECHA InfoCard	100.029.058
PubChem CID	82157;
UNII	40K942UPM8 ;
CompTox Dashboard (EPA)	DTXSID30889380 ;
	InChI InChI=1S/HNO5S/c2-1-6-7(3,4)5/h(H,3,4,5) Key: VQTGUFBGYOIUFS-UHFFFAOYSA-N ; InChI=1/HNO5S/c2-1-6-7(3,4)5/h(H,3,4,5) Key: VQTGUFBGYOIUFS-UHFFFAOYAM;
	SMILES O=NOS(=O)(=O)O;
Properties
Chemical formula	NOHSO4
Molar mass	127.08 g/mol
Appearance	Pale yellow crystals
Density	1.865 g/mL in; 40% sulfuric acid soln
Melting point	70 °C (158 °F; 343 K)
Boiling point	Decomposes
Solubility in water	Decomposes
Solubility	Soluble in H2SO4
Hazards
	Occupational safety and health (OHS/OSH):
Main hazards	Oxidizer
Related compounds
Other anions	NOCl
Other cations	NaHSO4
Related compounds	NOBF4
	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

Nitrosylsulfuric acid is the chemical compound with the formula NOHSO₄. It is a colourless solid that is used industrially in the production of caprolactam, and was formerly part of the lead chamber process for producing sulfuric acid. The compound is a salt best described as NO⁺HSO₄⁻ (nitrosonium hydrogensulfate). It is called “lead-chamber crystals”.

In organic chemistry, it is used as a reagent for nitrosating, as a diazotizing agent, and as an oxidizing agent.