:Potassium bifluoride

{{chembox

| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 470457569

| Name = Potassium bifluoride

| ImageFile = Potassium bifluoride.svg

| ImageFile1 = Sodium-bifluoride-xtal-3D-balls.png

| ImageSize = 150px

| IUPACName = Potassium bifluoride

| OtherNames = Potassium hydrogen difluoride

| Section1 = {{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo = 7789-29-9

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

| ChemSpiderID = 35308426

| EC_number = 232-156-2

| PubChem = 11829350

| RTECS = TS6650000

| UNNumber = 1811

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

| UNII = 880X05W53M

| StdInChI_Ref = {{stdinchicite|changed|chemspider}}

| StdInChI = 1S/F2H.K/c1-3-2;/q-1;+1

| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}

| StdInChIKey = FLCWRBFUWAZYGV-UHFFFAOYSA-N

| SMILES = [H-](F)F.[K+]

}}

| Section2 = {{Chembox Properties

| Formula = {{chem2|K[HF2]}}

| MolarMass = 78.103 g/mol

| Appearance = colourless solid

| Odor = slightly acidic

| Density = 2.37 g/cm³

| Solubility = {{ubl|24.5 g/(100 mL) (0 °C)|30.1 g/(100 mL) (10 °C)|39.2 g/(100 mL) (20 °C)|114.0 g/(100 mL) (80 °C)}}

| SolubleOther = soluble in ethanol

| MeltingPtC = 238.7

| BoilingPt = decomposes

}}

| Section3 = {{Chembox Structure

| Coordination =

| CrystalStruct = monoclinic

}}

| Section4 = {{Chembox Thermochemistry

| DeltaHf = −417.26 kJ/(mol·K)

| Entropy = 45.56 J/(mol·K) {{cite journal|last2 = Pitzer | first2 = Kenneth S. | first1 = Edgar F. Jr. | last1 = Westrum|title=Thermodynamics of the System KHF2-KF-HF, Including Heat Capacities and Entropies of KHF2, and KF. The Nature of the Hydrogen Bond in KHF2|journal=J. Am. Chem. Soc.|date=June 1949|volume=71| issue = 6 |pages=1940–1949|doi=10.1021/ja01174a012}}

}}

| Section7 = {{Chembox Hazards

| ExternalSDS =

| GHS_ref={{cite web |title=Potassium bifluoride |url=https://pubchem.ncbi.nlm.nih.gov/compound/11829350#section=Safety-and-Hazards |website=pubchem.ncbi.nlm.nih.gov |access-date=27 December 2021 |language=en}}

| GHSPictograms = {{GHS05}}{{GHS06}}

| GHSSignalWord = Danger

| HPhrases = {{H-phrases|301|310|314}}

| PPhrases = {{P-phrases|260|262|264|270|280|301+310|301+330+331|302+350|303+361+353|304+340|305+351+338|310|321|322|330|361|363|405|501}}

| FlashPt = non flammable

}}

| Section8 = {{Chembox Related

| OtherAnions = Potassium fluoride

| OtherCations = Sodium bifluoride, ammonium bifluoride

}}

}}

Potassium bifluoride is the inorganic compound with the formula {{chem2|K[HF2]}}. This colourless salt consists of the potassium cation ({{chem2|K+}}) and the bifluoride anion ({{chem2|[HF2]-}}). The salt is used as an etchant for glass. Sodium bifluoride is related and is also of commercial use as an etchant as well as in cleaning products.{{Ullmann|doi=10.1002/14356007.a11_307|title=Fluorine Compounds, Inorganic|year=2000|last1=Aigueperse|first1=Jean|last2=Mollard|first2=Paul|last3=Devilliers|first3=Didier|last4=Chemla|first4=Marius|last5=Faron|first5=Robert|last6=Romano|first6=René|last7=Cuer|first7=Jean Pierre|isbn=3527306730}}