Potassium hexafluorophosphate

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ImageFile = Potassium hexafluorophosphate.png ImageSize = 150px
IUPACName = Potassium hexafluorophosphate
OtherNames =
Section1 = Chembox Identifiers
CASNo = 17084-13-8
PubChem =
SMILES =

Section2 = Chembox Properties
Formula = F₆KP
MolarMass = 184.06
Appearance = colourless solid
Density = 2.75 g/mL
MeltingPt = 575 °C
BoilingPt =
Solubility = 0.432M (25 °C)
Section3 = Chembox Hazards
MainHazards = toxic
FlashPt =
Autoignition =

Potassium hexafluorophosphate is the chemical compound with the formula KPF₆. This colourless salt consists of potassium cations and hexafluorophosphate anions. It is prepared by the reaction: [cite journal | author = Woyski, M. M. | title = Hexafluorophosphates of Sodium, Ammonium, and Potassium | journal = Inorg. Synth. | volume = 3 | pages = 111–117 | doi = 10.1002/9780470132340.ch29 | year = 1950] :PCl₅ + KCl + 6 HF → KPF₆ + 6 HClThis exothermic reaction is conducted in liquid hydrogen fluoride. The salt is stable in hot alkaline aqueous solution, from which it can be recrystallized. The sodium and ammonium salts are more soluble in water whereas the rubidium and caesium salts are less so.

KPF₆ is a common laboratory source of the hexafluorophosphate anion, a non-coordinating anion that confers lipophilicity to its salts. It salts are often less soluble than the closely related tetrafluoroborates.

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