Copper (II) azide

from Wikipedia, the free encyclopedia
Structural formula
Structure of the Cu2 + ion     2 Structure of the azide ion
General
Surname Copper (II) azide
other names

Copper azide

Molecular formula Cu (N 3 ) 2
External identifiers / databases
CAS number 14215-30-6
PubChem 24745345
Wikidata Q421588
properties
Molar mass 147.59 g mol −1
Physical state

firmly

density

2.60 g cm −3

Melting point

explodes at 215 ° C

solubility

practically insoluble in water (80 mg l −1 at 20 ° C)

safety instructions
GHS hazard labeling
no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Copper azide is the copper salt of hydrazoic acid . It is explosive and is not used because of its high sensitivity to friction and pressure.

Manufacture and modifications

Copper azide

According to Urbanski , four modifications are known: The anhydrous compound is brown with a reddish glow. The green modification results from the action of hydrazoic acid on cupric hydroxide or cupric oxide . Sometimes it is more of a gray color. Heating in water leads to hydrolysis with the formation of basic copper azides of yellow color.

Brown-yellow modification

By reacting copper sulfate trihydrate with sodium azide or lithium azide

or by the action of a dilute hydrazoic acid to metallic copper produced by Theodor Curtius brown-yellow, slightly soluble in water crystals of anhydrous copper (II) azide in shape.

Green modification

It is formed by the action of hydrazoic acid on copper hydroxide or ( Straumanis and Cirulis ) on copper (II) oxide. Sometimes it's a more gray color.

Yellow modification

Heating in water ( Wöhler and Krupko, 1913) leads to hydrolysis with the formation of basic copper azides. According to Straumanis and Cirulis, very long heating causes complete hydrolysis, with copper oxide and free acids being released.

Substance data

Complex salts

The complex salts of copper azide are also explosive. The salt Cu (NH 3 ) 4 (N 3 ) 2 is significantly less sensitive to impact (1 kg from a height of 20 cm). The complex lithium hexaazidocuprate (II) Li 4 [Cu (N 3 ) 6 ] has exceptionally strong initiation properties .

use

Copper azide is one of the initial explosives . The green modification is the most sensitive. It often explodes when touched. Under the 2 kg drop hammer it explodes at a height of less than 1 cm. The black / brown modification at 1 cm and the yellow with a 1 kg drop hammer from 7 to 8 cm. The high initiating capacity for Nitropenta is noteworthy , whereby only 0.4 mg of copper azide are sufficient to detonate the Nitropenta . Copper azide is of great importance in practice, as it can be formed in addition to copper (I) azide with prolonged exposure to lead azide on copper or its alloys. Heavy metal azides are used as oxidizing agents in the laboratory.

Copper azide does not have a smooth surface, but rather forms grooves with a width of 5 nm (in the 110 direction). This property can be used to manufacture nanowires from iron , palladium or gold by vapor deposition .

safety instructions

Copper (II) azide is very sensitive and explodes under low pressure or friction. Since there are safer explosives available, it should neither be manufactured nor used.

References and comments

  1. ↑ a b c D. L. Perry (ed.), SL Phillips (ed.): Handbook of Inorganic Compounds , 1995 , ISBN 978-0-8493-8671-8 .
  2. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
  3. ↑ Ph. Naoum, Phokion P. Naoúm, Theodor Steinkopff: Schiess- und Sprengstoffe , 1927 ( limited preview in the Google book search).
  4. ↑ JF Finklea: Current Intelligence Bulletin 13 Explosive Azide Hazard , from: Current Intelligence Bulletin 13, NIOSH, US Department of Health and Human Services, Cincinnati, Ohio, 5 pages, 3 references, 1976.
  5. ↑ Georg Brauer , with the collaboration of Marianne Baudler a . a. (Ed.): Handbook of Preparative Inorganic Chemistry . 3rd, revised edition. tape I . Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6 , pp. 985 .
  6. ↑ Th. Curtius, J. Rissom: New investigations on the nitrogen hydrogen N 3 H. In: Journal for practical chemistry . 1898, 58, 1, pp. 261-309, doi: 10.1002 / prac.18980580113 .
  7. ↑ Wojciech Pawlowski Andrzej Radomski Explosives Information from the Polish Police, page 21/22 Cu (N3) 2 Explosion speed and other values ​​(Polish accessed on September 8, 2009).
  8. ↑ X.-D. Ma, DI Bazhanov, O. Fruchart, F. Yildiz, T. Yokoyama, M. Przybylski, VS Stepanyuk, W. Hergert, J. Kirschner: Strain Relief Guided Growth of Atomic Nanowires in a Cu 3 bN-Cu (110) Molecular Network . In: Physical Review Letters . tape 102 , no. 20 , 2009, p. 205503 , doi : 10.1103 / PhysRevLett.102.205503 ( archives-ouvertes.fr [PDF]).

literature

  • T. Urbanski: Chemistry and Technology of Explosives. Volume 3. German publishing house for basic industry, 1964.