Potassium hydride

Crystal structure
	__ K + __ H -
General
Surname	Potassium hydride
Ratio formula	KH
Brief description	gray solid
External identifiers / databases
EC number	231-704-8
ECHA InfoCard	100,028,823
PubChem	82127
Wikidata	Q6036
properties
Molar mass	40.11 g mol −1
Physical state	firmly
density	1.45 g cm 3 (20 ° C)
Melting point	420 ° C (decomposition, 1 atm. H 2 pressure)
solubility	violent decomposition in water
safety instructions
H and P phrases	H: 260-314
	EUH: 014
	P: 280-301 + 330 + 331-305 + 351 + 338-308 + 310-402 + 404
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Potassium hydride is an inorganic chemical compound of potassium from the group of hydrides .

Extraction and presentation

Potassium hydride forms slowly from the elements potassium and hydrogen from 260 ° C, with sufficient speed from 350 ° C. In contrast, sodium hydride is already formed from 80 ° C, with sufficient speed from 250 ° C.

{\ displaystyle \ mathrm {2 \ K + H_ {2} \ longrightarrow 2 \ KH}}

use

Since potassium hydride is a very strong base , it can be used to deprotonate organic molecules. Although it is more reactive than sodium hydride, it is less used in the laboratory due to the cumbersome handling.

safety instructions

Potassium hydride reacts with water to form hydrogen gas:

{\ displaystyle {\ ce {KH + H2O -> KOH + H2}}}

The reaction can generate so much heat that the hydrogen gas ignites. Potassium hydride is therefore sold by the manufacturers as a dispersion in mineral oil. According to a study, homogenization with paraffin is possible.

Individual evidence

↑ ^a ^b ^c ^d Data sheet potassium hydride (35% suspension in paraffin oil) for synthesis (PDF) from Merck , accessed on October 7, 2019.
^ AF Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 , p. 1279.
↑ Template: CL Inventory / not harmonized There is not yet a harmonized classification for this substance . A labeling of potassium hydride in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), retrieved on October 7, 2019, is reproduced from a self-classification by the distributor .
↑ Douglass F. Taber, Christopher G. Nelson: Potassium Hydride in Paraffin: A Useful Base for Organic Synthesis . In: The Journal of Organic Chemistry . tape 71 , no. 23 , 2006, p. 8973–8974 , doi : 10.1021 / jo061420v , PMC 3248818 (free full text).

[merck-1] Data sheet potassium hydride (35% suspension in paraffin oil) for synthesis (PDF) from Merck , accessed on October 7, 2019.

[2] AF Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 , p. 1279.

[3] Template: CL Inventory / not harmonized There is not yet a harmonized classification for this substance . A labeling of potassium hydride in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), retrieved on October 7, 2019, is reproduced from a self-classification by the distributor .

[4] Douglass F. Taber, Christopher G. Nelson: Potassium Hydride in Paraffin: A Useful Base for Organic Synthesis . In: The Journal of Organic Chemistry . tape 71 , no. 23 , 2006, p. 8973–8974 , doi : 10.1021 / jo061420v , PMC 3248818 (free full text).