Nitrosylsulfuric acid

{{Chembox

|Watchedfields = changed

|verifiedrevid = 434912557

|Name = Nitrosylsulfuric acid

|ImageFile = Nitrosylsulfuric acid structure.svg

|ImageAlt = Structural formula of nitrosylsulfuric acid

|ImageFile1 = Nitrosylsulfuric acid molecule ball.png

|ImageSize1 = 190px

|ImageAlt1 = Ball-and-stick model of the nitrosylsulfuric acid molecule

|IUPACName = Nitrosylsulfuric acid

|OtherNames = nitrosonium bisulfate, chamber crystals

|Section1={{Chembox Identifiers

|SMILES = O=NOS(=O)(=O)O

|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

|ChemSpiderID = 74147

|PubChem = 82157

|InChI = 1/HNO5S/c2-1-6-7(3,4)5/h(H,3,4,5)

|InChIKey = VQTGUFBGYOIUFS-UHFFFAOYAM

|StdInChI_Ref = {{stdinchicite|correct|chemspider}}

|StdInChI = 1S/HNO5S/c2-1-6-7(3,4)5/h(H,3,4,5)

|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

|StdInChIKey = VQTGUFBGYOIUFS-UHFFFAOYSA-N

|CASNo_Ref = {{cascite|correct|??}}

|CASNo = 7782-78-7

|UNII_Ref = {{fdacite|correct|FDA}}

|UNII = 40K942UPM8

}}

|Section2={{Chembox Properties

|Formula = {{chem2|HSO4NO}}

|MolarMass = 127.08 g/mol

|Appearance = Pale yellow crystals{{cite book |chapter= Nitrosylsulfuric Acid |author= George A. Olah, G. K. Surya Prakash, Qi Wang, Xing-Ya Li |title= Encyclopedia of Reagents for Organic Synthesis |doi= 10.1002/047084289X.rn060 |journal= E-EROS Encyclopedia of Reagents for Organic Synthesis |year= 2001 |isbn= 978-0471936237}}

|Density = 1.865 g/mL in
40% sulfuric acid soln {{cite web |url=https://www.sigmaaldrich.com/AT/de/product/aldrich/517070 | title=Nitrosylsulfuric acid solution | publisher=Merck}}

|Solubility = Decomposes

|SolubleOther = Soluble in H₂SO₄

|MeltingPtC = 70

|MeltingPt_ref =

|BoilingPt = Decomposes

}}

|Section7={{Chembox Hazards

|MainHazards = Oxidizer

}}

|Section8={{Chembox Related

|OtherAnions = NOCl

|OtherCations = NaHSO₄

|OtherCompounds = NOBF₄

}}

}}

Nitrosylsulfuric acid is the chemical compound with the formula {{chem2|HSO4NO}}. It is a colourless solid that is used industrially in the production of caprolactam,{{cite encyclopedia |author1=Ritz, J. |author2=Fuchs, H. |author3=Kieczka, H. |author4=Moran, W. C. |encyclopedia= Ullmann's Encyclopedia of Industrial Chemistry |publisher= Wiley-VCH |location= Weinheim |year= 2002 |doi= 10.1002/14356007.a05_031 |chapter=Caprolactam |isbn=978-3527306732}} and was formerly part of the lead chamber process for producing sulfuric acid. The compound is the mixed anhydride of sulfuric acid and nitrous acid.

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