Cadmium cyanide

Structural formula
General
Surname	Cadmium cyanide
other names	Cadmium (II) cyanide
Molecular formula	Cd (CN) 2
Brief description	white powder or rhombuses
External identifiers / databases
EC number	208-829-1
ECHA InfoCard	100.008.027
PubChem	68335
Wikidata	Q410497
properties
Molar mass	164.45 g mol −1
Physical state	firmly
density	2.226 g cm −3
Melting point	> 200 ° C (decomposition)
solubility	slightly soluble in water (17.1 g l −1 at 15 ° C); soluble in KCN solution;
safety instructions
H and P phrases	H: 330-310-300-351-373-410
	EUH: 032
	P: ?
Toxicological data	16 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 .

Cadmium cyanide is a chemical compound of cadmium from the group of cyanides .

Extraction and presentation

Cadmium cyanide can be obtained by dissolving cadmium hydroxide in aqueous hydrogen cyanide and then evaporating it.

{\ displaystyle \ mathrm {Cd (OH) _ {2} +2 \ HCN \ longrightarrow Cd (CN) _ {2} +2 \ H_ {2} O}}

It can also be precipitated from an aqueous solution of a cadmium salt (e.g. cadmium sulfate ) with an alkali metal cyanide (e.g. potassium cyanide ).

{\ displaystyle \ mathrm {CdSO_ {4} +2 \ KCN \ longrightarrow Cd (CN) _ {2} + K_ {2} SO_ {4}}}

properties

Cadmium cyanide is a non-flammable white powder which turns brown when heated and decomposes at temperatures above 200 ° C. It is also slowly decomposed in moist air containing carbon dioxide, releasing hydrogen cyanide. Cadmium cyanide has a cubic crystal structure of the copper (I) oxide type (a = 6.32 Å). It is sparingly soluble in water, but soluble in potassium cyanide, whereby potassium tetracyanocadmat (II) K ₂ [Cd (CN) ₄ ] is formed.

use

Cadmium cyanide is used for plating (i.e. as protection against corrosion) of metals.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g Entry for CAS no. 542-83-6 in the GESTIS substance database of the IFA , accessed on November 22, 2019 (JavaScript required)
↑ ^a ^b ^c ^d Georg Brauer (Ed.), With the collaboration of Marianne Baudler a . a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume II, Ferdinand Enke, Stuttgart 1978, ISBN 3-432-87813-3 .
↑ Entry on cadmium cyanide in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on November 22, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .
↑ Amit Arora; Textbook of Inorganic Chemistry; P. 756; ISBN 978-81-8356-013-9
↑ LJ Durney; Electroplating Engineering Handbook, pp. 236ff; ISBN 978-0-412-74110-4

[GESTIS-1] ↑ ^a ^b ^c ^d ^e ^f ^g Entry for CAS no. 542-83-6 in the GESTIS substance database of the IFA , accessed on November 22, 2019 (JavaScript required)

[brauer-2] Georg Brauer (Ed.), With the collaboration of Marianne Baudler a . a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume II, Ferdinand Enke, Stuttgart 1978, ISBN 3-432-87813-3 .

[CLP_100.008.027-3] Entry on cadmium cyanide in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on November 22, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .

[4] Amit Arora; Textbook of Inorganic Chemistry; P. 756; ISBN 978-81-8356-013-9

[5] LJ Durney; Electroplating Engineering Handbook, pp. 236ff; ISBN 978-0-412-74110-4