potassium amide
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| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 443791794
| ImageFile1 = Potassium-amide-2D-ionic.svg
| ImageFile1_Ref = {{Chemboximage|correct|??}}
| ImageSize1 =
| ImageName1 = Structural formula of potassium amide
| ImageFile2 = Potassium-amide-K-coordination-3D-balls.png
| ImageFile2_Ref = {{Chemboximage|correct|??}}
| ImageSize2 =
| ImageName2 = subunit of {{chem2|KNH2*2NH3}} emphasizing the coordination sphere of potassium
| IUPACName = Potassium amide
| OtherNames = Potassamide
|Section1={{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 17242-52-3
| PubChem = 87015
| EINECS = 241-275-9
| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}
| ChemSpiderID = 78490
| SMILES = [NH2-].[K+]
| InChI = 1/K.H2N/h;1H2/q+1;-1
| InChIKey = FEMRXDWBWXQOGV-UHFFFAOYAQ
| StdInChI_Ref = {{stdinchicite|changed|chemspider}}
| StdInChI = 1S/K.H2N/h;1H2/q+1;-1
| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
| StdInChIKey = FEMRXDWBWXQOGV-UHFFFAOYSA-N
}}
|Section2={{Chembox Properties
| Formula = {{chem2|KNH2}}
| K=1|N=1|H=2
| Appearance = white solid
| Odor = ammonia-like
| Density = 1.57 g/cm 3
| MeltingPtC = 338
| BoilingPt =
| Solubility = reacts
| SolubleOther = ammonia: 3.6 g/(100 mL)
}}
|Section4={{Chembox Thermochemistry
| DeltaHf = −128.9 kJ/mol
}}
|Section7={{Chembox Hazards
| MainHazards =
| NFPA-H = | NFPA-F = | NFPA-R = | NFPA-S =
| FlashPt =
| AutoignitionPt =
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|Section8={{Chembox Related
| OtherCations = Lithium amide
Sodium amide
}}
}}
Potassium amide is an inorganic compound with the chemical formula {{chem2|KNH2}}. Like other alkali metal amides, it is a white solid that hydrolyzes readily. It is a strong base.{{Cite book|doi = 10.1002/047084289X.rp193|chapter = Potassium Amide|title = Encyclopedia of Reagents for Organic Synthesis|year = 2001|last1 = Takaki|first1 = Katherine S.|isbn = 0471936235}}
Production
Potassium amide is produced by the reaction of ammonia with potassium. The reaction typically requires a catalyst.{{cite book|author=O. Glemser, H. Sauer|chapter=Silver Amide |title=Handbook of Preparative Inorganic Chemistry, 2nd Ed. |editor=G. Brauer|publisher=Academic Press|year=1963|place=NY, NY|volume=1|pages=1043}}
Structure
Traditionally {{chem2|KNH2}} is viewed as a simple salt, but it has significant covalent character and is highly aggregated in ammonia solution.{{citation needed|date=June 2022}} The compound has been characterized by X-ray crystallography as the solvent-free form{{cite journal |doi=10.1002/zaac.19653380309|title=Die Kristallstrukturen der Tieftemperaturmodifikationen von Kalium- und Rubidiumamid|year=1965|last1= Juza|first1=R.|last2=Jacobs|first2=H.|last3 =Klose|first3= W.|journal=Zeitschrift für Anorganische und Allgemeine Chemie|volume=338|issue=3–4|pages=171–178}} as well as the mono- and diammonia solvates. In {{chem2|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–{{chem2|NH2}} distances are 2.7652(11) whereas the K–{{chem2|NH3}} distances are respectively 2.9234(11) and 3.0698(11) Å.{{cite journal |doi=10.1002/zaac.200400467|title=Hydrogen Bonds in Potassium Amide-Ammonia(1/2), KNH2.2NH3|year=2005|last1=Kraus|first1=Florian|last2=Korber|first2=Nikolaus|journal=Zeitschrift für Anorganische und Allgemeine Chemie|volume=631|issue=6–7|pages=1032–1034}}
References
{{Potassium compounds}}
{{inorganic-compound-stub}}