Hydroxylamine

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hydroxylamine

[‚hī‚dräk′sil·ə‚mēn]
(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.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Hydroxylamine

 

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.

REFERENCE

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

V. S. LAPIK

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
This report describes laboratory trials of 17 other hydroxylamine derivatives against white- and brown-rot fungi.
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.
This work focuses on the formation of tertiary carbinamine centers via a 2,3-rearrangement of hydroxylamine allyl ethers.
[6] studied the direct oxidation of ammonia to hydroxylamine with high yield at low temperature and atmospheric pressure, in which hydrogen peroxide was used as oxidant, Ti-silicalite was used as catalyst.
The catalyst interacts with hydroxylamine in acidic medium and generates protonated amino (*NH3+) radical, which was the active aminating species, by reduction of hydroxylamine.
Hu, Sodium Metavanadate Catalyzed One-Step Amination of Benzene to Aniline with Hydroxylamine, J.