Potassium hexafluorophosphate

Structural formula
General
Surname	Potassium hexafluorophosphate
other names	Potassium phosphorus hexafluoride
Molecular formula	K [PF 6 ]
Brief description	white solid
External identifiers / databases
CAS number 17084-13-8 EC number 241-143-0 ECHA InfoCard 100.037.388 PubChem 23688904 Wikidata Q1910594
properties
Molar mass	184.06 g mol −1
Physical state	firmly
density	2.75 g cm −3 (25 ° C)
Melting point	575 ° C
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 314 P: 280-305 + 351 + 338-310
Toxicological data	1400 mg kg −1 ( LD 50 ,  rat ,  oral )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Potassium hexafluorophosphate is an inorganic chemical compound of potassium from the group of hexafluorophosphates .

Extraction and presentation

Potassium hexafluorophosphate can be obtained by reacting tetrachlorophosphonium hexafluorophosphate with potassium hydroxide .

${\displaystyle \mathrm {PCl_{4}\cdot PF_{6}+7\ KOH\longrightarrow K[PF_{6}]+K_{2}[HPO_{4}]+4\ KCl+3\ H_{2}O} }$

It can also be made by reacting phosphorus pentafluoride with potassium fluoride .

${\displaystyle \mathrm {PF_{5}+KF\longrightarrow K[PF_{6}]} }$

It is also possible to obtain it by reacting phosphorus pentachloride with potassium chloride and hydrogen fluoride . This reaction can also be used to prepare analogous compounds such as sodium hexafluorophosphate or ammonium hexafluorophosphate .

${\displaystyle \mathrm {PCl_{5}+KCl+6\ HF\longrightarrow K[PF_{6}]+6\ HCl} }$

properties

Potassium hexafluorophosphate is a colorless solid that comes in the form of square and rectangular thick sheets. It melts when it is red hot with partial decomposition. When heated with solid sodium hydroxide , vigorous conversion to fluoride and phosphate takes place above 400 ° C. It has a crystal structure with a face-centered cubic lattice and the space group Pa3. The transition to a different crystal structure occurs below −25 ° C.

See also

• Ammonium hexafluorophosphate
• Lithium hexafluorophosphate
• Sodium hexafluorophosphate
• Silver hexafluorophosphate

Individual evidence

1. ↑ ^{a b c d e f} data sheet Potassium hexafluorophosphate, 99.5% trace metals basis from Sigma-Aldrich , accessed on September 23, 2013 ( PDF ).
2. ^ JH Simons: Fluorine Chemistry . Elsevier, 1965, ISBN 0-323-14245-1 , pp. 39 ( limited preview in Google Book search).
3. ↑ ^{a b} Georg Brauer (Ed.), With the collaboration of Marianne Baudler u a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6 , p. 215.
4. ^ William George Palmer: Experimental Inorganic Chemistry . CUP Archive, 1970, ISBN 0-521-05902-X , p. 266 ( limited preview in Google Book search).
5. ^ Harry Julius Emeléus: The chemistry of fluorine and its compounds . Academic Press, 1969, pp. 102 ( limited preview in Google Book search).
6. ^ Jean d'Ans, Ellen Lax, Roger Blachnik: Pocket book for chemists and physicists . Springer DE, 1998, ISBN 3-642-58842-5 , pp. 514 ( limited preview in Google Book search).