Potassium amide

Potassium amide
Names


IUPAC name Potassium amide
Other names Potassamide Kaliamide
Identifiers
CAS Number	17242-52-3^Y
3D model (JSmol)	Interactive image
ChemSpider	78490^N
ECHA InfoCard	100.037.508
EC Number	241-275-9
PubChem CID	87015
CompTox Dashboard (EPA)	DTXSID4066177
InChI InChI=1S/K.H2N/h;1H2/q+1;-1^N Key: FEMRXDWBWXQOGV-UHFFFAOYSA-N^N InChI=1/K.H2N/h;1H2/q+1;-1 Key: FEMRXDWBWXQOGV-UHFFFAOYAQ
SMILES [NH2-].[K+]
Properties
Chemical formula	KNH₂
Molar mass	55.121 g·mol⁻¹
Appearance	white solid
Odor	ammonia-like
Density	1.57 g/cm ³
Melting point	338 °C (640 °F; 611 K)
Solubility in water	reacts
Solubility	ammonia: 3.6 g/(100 mL)
Thermochemistry
Std enthalpy of formation (Δ_fH^⦵₂₉₈)	-128.9 kJ/mol
Related compounds
Other cations	Lithium amide Sodium amide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is ^YN ?) Infobox references

Chemical compound

Potassium amide is an inorganic compound with the chemical formula KNH₂. Like other alkali metal amides, it is a white solid that hydrolyzes readily. It is a strong base.^[1]

Production

Potassium amide is produced by the reaction of ammonia with potassium. The reaction typically requires a catalyst.^[2]

Structure

Traditionally KNH₂ is viewed as a simple salt, but it has significant covalent character and is highly aggregated in ammonia solution.^{[citation needed]} The compound has been characterized by X-ray crystallography as the solvent-free form^[3] as well as the mono- and diammonia solvates. In KNH₂·2NH₃, the potassium centers are each bonded to two amido ligands and four ammonia ligands, all six of which bridge to adjacent potassium centers. The result is a chain of hexacoordinate potassium ions. The K–NH₂ distances are 2.7652(11) whereas the K–NH₃ distances are respectively 2.9234(11) and 3.0698(11) Å.^[4]

References

^ Takaki, Katherine S. (2001). "Potassium Amide". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rp193. ISBN 0471936235.
^ O. Glemser, H. Sauer (1963). "Silver Amide". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 1. NY, NY: Academic Press. p. 1043.
^ Juza, R.; Jacobs, H.; Klose, W. (1965). "Die Kristallstrukturen der Tieftemperaturmodifikationen von Kalium- und Rubidiumamid". Zeitschrift für Anorganische und Allgemeine Chemie. 338 (3–4): 171–178. doi:10.1002/zaac.19653380309.
^ Kraus, Florian; Korber, Nikolaus (2005). "Hydrogen Bonds in Potassium Amide-Ammonia(1/2), KNH₂^.2NH₃". Zeitschrift für Anorganische und Allgemeine Chemie. 631 (6–7): 1032–1034. doi:10.1002/zaac.200400467.