Cyanogen

Names Preferred IUPAC nameSystematic IUPAC nameOther names Identifiers 1732464 ChEBIChemSpiderECHA InfoCard100.006.643EC Number1090 MeSHcyanogenRTECS numberUNIIUN number1026 Properties C₂N₂Molar mass52.036 g·mol Appearance Colourless gas Odorpungent, bitter almond-like Density950 mg/mL (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) Solubilitysoluble in ethanol, ethyl etherVapor pressure5.1 atm (21 °C) 1.9 μmol/(Pa·kg) −21.6·10 cm/mol 1.327 (18 °C) Thermochemistry 241.57 J/(K·mol) 309.07 kJ/mol −1.0978–−1.0942 MJ/mol Hazards Occupational safety and health (OHS/OSH): forms cyanide in the body; flammable GHS labelling: DangerH220, H331, H410P210, P261, P271, P273, P304+P340, P311, P321, P377, P381, P391, P403, P403+P233, P405, P501NFPA 704 (fire diamond) Explosive limits6.6–32% NIOSH (US health exposure limits): none TWA 10 ppm (20 mg/m) N.D. Safety data sheet (SDS) inchem.orgRelated compounds DBNPA

Cyanogen is the chemical compound with the formula(CN)₂. Its structure is N≡C−C≡N. The simplest stable carbon nitride, it is a colorless and highly toxicgas with a pungentodor. The molecule is a pseudohalogen. Cyanogen molecules are linear, and consist of two CN groups ‒ analogous to diatomic halogen molecules, such as Cl₂, but far less oxidizing. The two cyano groups are bonded together at their carbon atoms, though other isomers have been detected. The name is also used for the CN radical, and hence is used for compounds such as cyanogen bromide (Br−C≡N) (but see also Cyano radical). When burned at increased pressure with oxygen, it is possible to get a blue tinted flame, the temperature of which is about 4,800 °C (8,670 °F) (a higher temperature is possible with ozone). It is as such regarded as the gas with the second highest temperature of burning (after dicyanoacetylene).

Cyanogen is the anhydride of oxamide:

H₂N−C(=O)−C(=O)−NH₂ → N≡C−C≡N + 2 H₂O

Oxamide is manufactured from cyanogen by hydration:

N≡C−C≡N + 2 H₂O → H₂N−C(=O)−C(=O)−NH₂