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| Names | |
|---|---|
| Other names Trichloramine Agene Nitrogen(III) chloride Trichloroazane Trichlorine nitride | |
| Identifiers | |
3D model (JSmol) | |
| ChEBI | |
| ChemSpider |
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| ECHA InfoCard | 100.030.029 |
| EC Number |
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| 1840 | |
| RTECS number |
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| UNII | |
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| Properties | |
| NCl3 | |
| Molar mass | 120.36 g·mol−1 |
| Appearance | yellow oily liquid |
| Odor | chlorine-like |
| Density | 1.653 g/mL |
| Melting point | −40 °C (−40 °F; 233 K) |
| Boiling point | 71 °C (160 °F; 344 K) |
| immiscible slowly decomposes | |
| Solubility | soluble inbenzene,chloroform,CCl4,CS2,PCl3 |
| Structure | |
| orthorhombic (below −40 °C) | |
| trigonal pyramidal | |
| 0.6D | |
| Thermochemistry | |
Std enthalpy of formation(ΔfH⦵298) | 232 kJ/mol |
| Hazards | |
| NFPA 704 (fire diamond) | |
| 93 °C (199 °F; 366 K) | |
| Related compounds | |
Otheranions | Nitrogen trifluoride Nitrogen tribromide Nitrogen triiodide |
Othercations | Phosphorus trichloride Arsenic trichloride |
Relatedchloramines | Monochloramine Dichloramine |
Related compounds | Nitrosyl chloride |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Nitrogen trichloride, also known astrichloramine, is thechemical compound with theformulaNCl3. This yellow, oily, and explosive liquid is most commonly encountered as a product ofchemical reactions betweenammonia-derivatives andchlorine (for example, inswimming pools). Alongsidemonochloramine anddichloramine, trichloramine is responsible for the distinctive 'chlorine smell' associated with swimming pools, where the compound is readily formed as a product fromhypochlorous acid reacting withammonia and other nitrogenous substances in the water, such asurea fromurine.[1]
The compound is generated by treatment ofammonium chloride withcalcium hypochlorite. When prepared in an aqueous-dichloromethane mixture, the trichloramine is extracted into the nonaqueous phase.[2] Intermediates in this conversion includemonochloramine anddichloramine,NH2Cl andNHCl2, respectively.
Nitrogen trichloride, trademarked asAgene, was at one time used to bleachflour,[3] but this practice was banned in the United States in 1949 due to safety concerns.
Like ammonia,NCl3 is apyramidal molecule. The N-Cl distances are 1.42 Å, and the Cl-N-Cl angles are 107°.[4]
Nitrogen trichloride can form in small amounts when public water supplies are disinfected withmonochloramine, and in swimming pools by disinfecting chlorine reacting withurea in urine and sweat from bathers.
The chemistry ofNCl3 has been well explored.[5] It is moderatelypolar with adipole moment of 0.6 D. The nitrogen center is basic but much less so than ammonia. It ishydrolyzed by hot water to releaseammonia andhypochlorous acid.
Concentrated samples of NCl3 can explode to giveN2 andchlorine gas.[citation needed]
In the presence ofaluminium trichloride, NCl3 reacts with some branched hydrocarbons to produce, after a hydrolysis step,amines.[2][6]
Nitrogen trichloride can irritate mucousmembranes — it is alachrymatory agent, but has never been used as such.[7][8] The compound (rarely encountered) is a dangerous explosive, being sensitive to light, heat, even moderate shock, and organic compounds.Pierre Louis Dulong first prepared it in 1812, and lost several fingers and an eye in two explosions.[9] In 1813, anNCl3 explosion blinded SirHumphry Davy temporarily, inducing him to hireMichael Faraday as a co-worker. They were both injured in anotherNCl3 explosion shortly thereafter.[10]
