Cyanogen
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Names | |||
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Preferred IUPAC name
Oxalonitrile[4] | |||
Systematic IUPAC name
Ethanedinitrile[4] | |||
Other names | |||
Identifiers | |||
3D model (
JSmol ) |
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1732464 | |||
ChEBI | |||
ChemSpider | |||
ECHA InfoCard
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100.006.643 | ||
EC Number |
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1090 | |||
MeSH | cyanogen | ||
PubChem CID
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RTECS number
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UNII | |||
UN number | 1026 | ||
CompTox Dashboard (EPA)
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Properties | |||
C2N2 | |||
Molar mass | 52.036 g·mol−1 | ||
Appearance | Colourless gas | ||
Odor | pungent, almond-like | ||
Density | 950 mg mL−1 (at −21 °C) | ||
Melting point | −28 °C (−18 °F; 245 K) | ||
Boiling point | −21.1 °C; −6.1 °F; 252.0 K | ||
45 g/100 mL (at 20 °C) | |||
Solubility | soluble in ethyl ether
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Vapor pressure | 5.1 atm (21 °C)[5] | ||
Henry's law
constant (kH) |
1.9 μmol Pa−1 kg−1 | ||
-21.6·10−6 cm3/mol | |||
Refractive index (nD)
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1.327 (18 °C) | ||
Thermochemistry | |||
Std molar
entropy (S⦵298) |
241.57 J K−1 mol−1 | ||
Std enthalpy of (ΔfH⦵298)formation |
309.07 kJ mol−1 | ||
Std enthalpy of (ΔcH⦵298)combustion |
−1.0978–−1.0942 MJ mol−1 | ||
Hazards | |||
Occupational safety and health (OHS/OSH): | |||
Main hazards
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forms cyanide in the body; flammable[5] | ||
GHS labelling: | |||
Danger | |||
H220, H331, H410 | |||
P210, P261, P271, P273, P304+P340, P311, P321, P377, P381, P391, P403, P403+P233, P405, P501 | |||
NFPA 704 (fire diamond) | |||
Explosive limits
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6.6–32%[5] | ||
NIOSH (US health exposure limits): | |||
PEL (Permissible)
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none[5] | ||
REL (Recommended)
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TWA 10 ppm (20 mg/m3)[5] | ||
IDLH (Immediate danger) |
N.D.[5] | ||
Safety data sheet (SDS) | inchem.org | ||
Related compounds | |||
Related alkanenitriles
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Related compounds
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DBNPA | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Cyanogen is the
Cyanogen is the
- H2NC(O)C(O)NH2 → NCCN + 2 H2O
although oxamide is manufactured from cyanogen by hydrolysis:[9]
- NCCN + 2 H2O → H2NC(O)C(O)NH2
Preparation
Cyanogen is typically generated from cyanide compounds. One laboratory method entails thermal decomposition of mercuric cyanide:
- 2 Hg(CN)2 → (CN)2 + Hg2(CN)2
Alternatively, one can combine solutions of copper(II) salts (such as copper(II) sulfate) with cyanides; an unstable copper(II) cyanide is formed which rapidly decomposes into copper(I) cyanide and cyanogen.[10]
- 2 CuSO4 + 4 KCN → (CN)2 + 2 CuCN + 2 K2SO4
Industrially, it is created by the
Isomers
Cyanogen is NCCN. There are less stable isomers in which the order of the atoms differs. Isocyanogen (or cyanoisocyanogen) is NCNC, diisocyanogen is CNNC, and diazodicarbon[citation needed] is CCNN.
Paracyanogen
Paracyanogen is a polymer of cyanogen. It can be best prepared by heating mercuric cyanide. It can also be prepared by heating silver cyanide, silver cyanate, cyanogen iodide or cyanuric iodide.[12] It can also be prepared by the polymerization of cyanogen at 300 to 500 °C (572 to 932 °F) in the presence of trace impurities. Paracyanogen can also be converted back to cyanogen by heating to 800 °C (1,470 °F).[9] Based on experimental evidence, the structure of this polymeric material is thought to be rather irregular, with most of the carbon atoms being of sp2 type and localized domains of π conjugation.[13]
History
Cyanogen was first synthesized in 1815 by Joseph Louis Gay-Lussac, who determined its empirical formula and named it. Gay-Lussac coined the word "cyanogène" from the Greek words κυανός (kyanos, blue) and γεννάω (gennao, I create), because cyanide was first isolated by the Swedish chemist Carl Wilhelm Scheele from the pigment "Prussian blue".[14] It attained importance with the growth of the fertilizer industry in the late 19th century and remains an important intermediate in the production of many fertilizers. It is also used as a stabilizer in the production of nitrocellulose.
Cyanogen is commonly found in
Safety
Like other
Cyanogen produces the second-hottest-known natural flame (after carbon subnitride) with a temperature of over 4,525 °C (8,177 °F) when it burns in oxygen.[19][20]
In popular culture
In the Doctor Who serial "The Brain of Morbius" (the 5th serial of season 13), the Doctor synthesizes cyanogen using hydrogen cyanide as a starting material and vents it through a pipe to stop Solon from performing surgery on the brain of Morbius's body.
In Dragnet (1987) Friday (Dan Aykroyd) and Streebek (Tom Hanks) are tracking down the villain who stole "the pseudohalogenic compound cyanogen".[21]
See also
References
- ^ "oxalonitrile (CHEBI:29308)". Chemical Entities of Biological Interest. UK: European Bioinformatics Institute. 27 October 2006. Main. Retrieved 6 June 2012.
- ^ a b NIOSH Pocket Guide to Chemical Hazards. Department of Health and Human Services, Centers for Disease Control, National Institute for Occupational Safety & Health. September 2007. p. 82.
- ^ ISBN 9780911910278.
- ^ ISBN 978-0-85404-182-4.
- ^ a b c d e f NIOSH Pocket Guide to Chemical Hazards. "#0161". National Institute for Occupational Safety and Health (NIOSH).
- .
- ISBN 978-3-642-11271-3.
- ^ Hartman, W. W.; Dreger, E. E. (1931). "Cyanogen Bromide" (PDF). Organic Syntheses. 11: 30; Collected Volumes, vol. 2, p. 150.
- ^ ISBN 978-0-08-037941-8.
- .
- .
- .
- .
- ^ Gay-Lussac, J. L. (1815). "Recherches sur l'acide prussique". Annales de Chimie (in French). 95: 136–231. Gay-Lussac names cyanogen on p. 163.
- ^ a b "Cometary Poison Gas Geyser Heralds Surprises". science.nasa.gov. 2010-11-02. Archived from the original on 2010-11-06.
- ^ "Comet's Poisonous Tail" (PDF). New York Times. 1910-02-08.
- ^ "Halley's Comet 100 years ago". The Denver Post. 2010-05-25.
- ^ Muir, G. D., ed. (1971). Hazards in the Chemical Laboratory. London: The Royal Institute of Chemistry.
- .
- .
- ^ "The trichlornitromethane and the pseudo-halogenic compound cyanogen". Retrieved August 18, 2021.
External links
- Media related to Cyanogen at Wikimedia Commons
- Chisholm, Hugh, ed. (1911). . Encyclopædia Britannica (11th ed.). Cambridge University Press.
- National Pollutant Inventory - Cyanide compounds fact sheet
- PhysOrg.com
- CDC - NIOSH Pocket Guide to Chemical Hazards