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(inorganic chemistry)
NH2OH A colorless, crystalline compound produced commercially by acid hydrolysis of nitroparaffins, decomposes on heating, melts at 33°C; used in organic synthesis and as a reducing agent.



H2NOH, is the product of the replacement of one hydrogen atom in the ammonia molecule (NH3) by an OH group. It forms colorless acicular crystals. Density, 1,204.4 kg/m3 (at 23.5° C); melting point, 33°-34° C; boiling point, 58° C at 2.933 kilonewtons per sq m (22 mm Hg). Hydroxylamine is stable at 0° C; at 20° C it decomposes slowly. An increase in temperature accelerates the decomposition, and at 130° C it explodes.

Hydroxylamine is hygroscopic. It dissolves readily in water to form hydroxylamine hydrate, which is a weak base: NH2OH·H2O ⇆ NH3OH+ + OH. Upon reaction with acids, hydroxylamine hydrate gives hydroxyammonium salts—for example, NH3OHCl and (NH3OH)2SO4—which have strong reducing properties. Hydroxylamine dissolves readily in methyl and ethyl alcohols but is insoluble in acetone, benzene, and petroleum ether. It is oxidized by atmospheric oxygen to HNO2. Hydroxylamine sulfate is produced industrially by reducing sodium nitrite with sulfur dioxide in the presence of sodium carbonate. Free hydroxylamine is produced by distilling alkaline solutions of the salts. Hydroxylamine and its derivatives are poisonous. Salts of hydroxylamine are extensively used in the pharmaceutical industry, in making kapron, and in analytical chemistry.


Brikum, I. K., M. T. Kozlovskii, and L. V. Nikitina. Gidrazin igidroksilamin i ikh primenenie v analiticheskoi khimii. Alma-Ata, 1967.


References in periodicals archive ?
trabeum often exceeded 50 percent, suggesting that most of the hydroxylamine derivatives had little protective effect.
These results suggest that the hydroxylamine derivatives used in our study lacked the protective effects found by Green et al.
The hydroxylamine derivatives evaluated were apparently incapable of providing consistent protection to ponderosa pine blocks against white-rot or brown-rot fungi under the conditions employed.
The organic thermochemistry of hydroxylamines, oximes, hydroxamic acids and their derivatives
NMR spectra of hydroxylamines, oximes and hydroxamic acids
Electrophilic C-amination with O-substituted hydroxylamines, oximes and O-substituted oximes
Rearrangements of hydroxylamines, oximes and hydroxamic acids
Electrochemistry of hydroxylamines, oximes and hydroxamic acids
Hu, Sodium Metavanadate Catalyzed One-Step Amination of Benzene to Aniline with Hydroxylamine, J.
Cheng, Amination of Benzene and Toluene with Hydroxylamine in the Presence of Transition Metal Redox Catalysts, J.