Potassium azide

Crystal structure
__ Rb +      __ N 1 / 3−
Crystal system	tetragonal
Space group	I 4 / mcm (No. 140)
Lattice parameters	a = 6.1129 Å, c = 7.0943 Å
General
Surname	Potassium azide
Ratio formula	CN 3
Brief description	colorless solid
External identifiers / databases
CAS number 20762-60-1 EC number 244-013-1 ECHA InfoCard 100.039.997 PubChem 10290740 Wikidata Q1093446
properties
Molar mass	81.12 g mol −1
Physical state	firmly
density	2.038 g · cm −3
Melting point	355 ° C (decomposition)
solubility	soluble in water (496 g l −1 at 17 ° C) and ethanol insoluble in ether
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 300 P: 264-301 + 310
Toxicological data	27 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 is the potassium salt of hydrogen azide and belongs to the group of azides .

Extraction and presentation

Potassium can be obtained by reaction of hydrogen azide and potassium hydroxide are obtained.

${\displaystyle {\ce {HN3 + KOH -> KN3 + H2O}}}$

It can also be obtained by reacting potassium carbonate with hydrazoic acid.

${\displaystyle {\ce {K2CO3 + 2HN3 -> 2KN3 + CO2 ^ + H2O}}}$

Description and characteristics

Potassium azide is a very toxic chemical that also reacts explosively when exposed to ultraviolet light or when heated to a great extent. It disproportionates to metallic potassium and nitrogen gas . Potassium azide is not sensitive to impact like heavy metal azides. The reaction equation works as follows:

${\displaystyle {\ce {2KN3 -> 2K + 3N2 ^}}}$

It crystallizes in a tetragonal crystal structure with the space group I 4 / mcm (space group no. 140) and Z = 4. with the lattice constants a = 6.1129 Å and c = 7.0943 Å.

See also

• Sodium azide

Individual evidence

1. ↑ ^{a b} Roger Blachnik (Ed.): Pocket book for chemists and physicists . Volume III: Elements, Inorganic Compounds and Materials, Minerals . founded by Jean d'Ans, Ellen Lax. 4th, revised and revised edition. Springer, Berlin 1998, ISBN 3-540-60035-3 , pp. 510 ( limited preview in Google Book Search).
2. ↑ ^{a b c} data sheet Potassium azide, ≥99.9% trace metals basis from Sigma-Aldrich , accessed on March 18, 2013 ( PDF ).
3. ↑ ^{a b c d} Georg Brauer (Ed.), With the collaboration of Marianne Baudler a . a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6 , p. 458.
4. ↑ EPA TSCA Chemical Substance Inventory : Section 8 (b), Potassium azide ; 1998.
5. ↑ Inorganic Syntheses . John Wiley & Sons, 2009, ISBN 0-470-13264-7 , pp. 79 ( limited preview in Google Book search).
6. ↑ Pradyot Patnaik: A Comprehensive Guide to the Hazardous Properties of Chemical Substances . John Wiley & Sons, 2007, ISBN 978-0-471-71458-3 , pp. 615 ( limited preview in Google Book search).
7. ^ ^{A b} C. C. Addison: Inorganic Chemistry of the Main-Group Elements . Royal Society of Chemistry, 1974, ISBN 0-85186-762-6 , pp. 54 ( limited preview in Google Book search).
8. ↑ Ulrich Müller: Refinement of the crystal structures of KN ₃ , RbN ₃ , CsN ₃ and TlN ₃ . In: Journal of Inorganic and General Chemistry . tape 392 , no. 2 , 1972, p. 159-166 , doi : 10.1002 / zaac.19723920207 .