Silver cyanide

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Structural formula
Silver ion   Cyanide ion
General
Surname Silver cyanide
Molecular formula AgCN
Brief description

white, odorless and tasteless hexagonal-rhombohedral crystals

External identifiers / databases
CAS number 506-64-9
EC number 208-048-6
ECHA InfoCard 100.007.317
PubChem 10475
Wikidata Q417298
properties
Molar mass 133.89 g mol −1
Physical state

firmly

density

3.95 g cm −3 (20 ° C)

Melting point

320 ° C (decomposition)

solubility

2.2 10 −5  % (water, 20 ° C)

safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary
06 - Toxic or very toxic 05 - Corrosive 09 - Dangerous for the environment

danger

H and P phrases H: 300 + 310 + 330-318-410
EUH: 032
P: 280-301 + 330 + 331-310-302 + 352-310-304 + 340 + 310
MAK

2 mg m −3

Thermodynamic properties
ΔH f 0

146.0 kJ / mol

As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Silver cyanide is the cyanide salt of silver . It has the formula AgCN.

presentation

Silver cyanide can be obtained by reacting a silver nitrate solution with a potassium cyanide solution.

properties

Silver cyanide is a colorless, odorless salt that decomposes when heated to 320 ° C. The decomposition of silver cyanide in the air produces hydrogen cyanide and nitrous gases as volatile products. Carbon dioxide is in the presence of moisture, as typical of cyanides from them cyanide -free. Like many cyanides , silver cyanide is highly toxic.

use

Silver cyanide is produced when silver is extracted from silver ores. The ore is treated with an aqueous sodium cyanide solution and air with oxygen , the silver being converted into silver cyanide, which combines with further cyanide to form the soluble complex dicyanoargentate [NC-Ag-CN] - . This process is called cyanide leaching . Silver cyanide is used, among other things, in electroplating (silvering) and in the production of isonitriles .

Individual evidence

  1. a b Entry on silver cyanide. In: Römpp Online . Georg Thieme Verlag, accessed on June 13, 2014.
  2. a b c d e f Entry on silver cyanide in the GESTIS substance database of the IFA , accessed on February 1, 2016 (JavaScript required)
  3. ^ D'Ans-Lax: paperback for chemists and physicists. 4th edition. Volume 3, Springer Verlag, 1998, ISBN 3-540-60035-3 .
  4. Not explicitly listed in Regulation (EC) No. 1272/2008 (CLP) , but with the indicated labeling it falls under the group entry salts of hydrogen cyanide with the exception of complex cyanides such as ferrocyanides, ferricyanides and mercuric oxycyanide and those specified elsewhere in this Annex in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
  5. David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Standard Thermodynamic Properties of Chemical Substances, pp. 5-18.
  6. 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. 629.