Potassium bisulfite: Difference between revisions

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| verifiedrevid = 325410066

| Name =

| ImageFile = Potassium bisulfite.svg

| ImageFile1 = Potassium-bisulfite-3D-balls.png

| ImageSize = 180px

| IUPACName = Potassium hydrogen sulfite

| OtherNames = {{Unbulleted list|Potassium bisulfite|potassium bisulphite|monopotassium salt|monopotassium sulfite|potassium hydrosulfite}}

| SystematicName =

| Section1 = {{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}

| ChemSpiderID = 22889

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

| UNII_Ref = {{fdacite|changed|FDA}}

| UNII = QJK5LO891P

| PubChem = 23663620

| EINECS = 231-870-1

| InChI = 1S/K.H2O3S/c;1-4(2)3/h;(H2,1,2,3)/q+1;/p-1

| SMILES = OS(=O)[O-].[K+]

| Section2 = {{Chembox Properties

| Odor = [[Sulfur dioxide|SO₂]]-like

| MeltingPtC = 190

| MeltingPt_notes = (decomposes)

| Solubility = 49{{nbsp}}g/100{{thinsp}}mL (20{{nbsp}}°C) <br> 115{{nbsp}}g/100{{thinsp}}mL (100{{nbsp}}°C)

| SolubleOther = Insoluble in alcohol

| Section3 = {{Chembox Hazards

| AutoignitionPt =

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'''Potassium bisulfite''' (or '''potassium hydrogen sulfite''') is a [[chemical]] mixture with the approximately correctly mentioned formula [[chemical formula]] KHSO₃. Potassium bisulfite in fact is not a real compound,<ref>{{cite journal|doi=10.1021/ed080p1482|bibcode=2003JChEd..80.1482T|title=New Methods to Estimate Lattice Energies: Application to the Relative Stabilities of Bisulfite (HSO₃⁻) and Metabisulfite (S₂O₅^2-) Salts|year=2003|last1=Tudela|first1=David|last2=Jenkins|first2=H. Donald B.|journal=Journal of Chemical Education|volume=80|issue=12|pages=1482}}</ref> but a mixture of salts that dissolve in water to give solutions composed of potassium ions and bisulfite ions. It is a white solid with an odor of [[sulfur dioxide]]. Attempts to crystallize potassium bisulfite yield [[potassium metabisulfite]], K₂S₂O₅.<ref>{{cite book|doi=10.1002/9780470132333.ch49|isbn=9780470132333|chapter=Sulfites and Pyrosulfites of the Alkali Metals|series=Inorganic Syntheses|year=1946|last1=Johnstone|first1=H. F.|title=Inorganic Syntheses|pages=162–167|volume=2}}</ref>

Potassium bisulfite is used as a sterilising agent in the production of alcoholic beverages.<ref>{{Ullmann|doi=10.1002/14356007.a25_477|isbn=3527306730|title=Sulfites, Thiosulfates, and Dithionitesl Chemistry|year=2000|last1=Barberá|first1=José Jiménez|last2=Metzger|first2=Adolf|last3=Wolf|first3=Manfred}}</ref> This additive is classified as [[E number]] E228 under the current EU-approved [[food additive]] legislation.<ref>{{Cite web|url=http://www.food.gov.uk/business-guidance/approved-additives-and-e-numbers|title=Approved additives and E numbers|website=Food Standards Agency|language=en|access-date=2020-04-07}}</ref>

==Production==

It is made by the reaction of [[sulfur dioxide]] and [[potassium carbonate]]. The sulfur dioxide is passed through a solution of the potassium carbonate until no more carbon dioxide is evolved. The solution is concentrated.

* [[Calcium bisulfite|sodium bisulfite]]

[[Category:E-number additives]]

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