Nitrogen dioxide properties

Synonyms Cellulose, oxidized Cellulosic acid Oxycellulose Definition Cellulose produced by treatment with nitrogen dioxide Properties SI. of-wh. gauze, lint, or powd. si. charred odor acid taste sol. in aq. org. bases, dll. alkali, ammonium hydroxide insol. in water, acids, common org. sol vs. 

Unlike nitrogen monoxide, nitrogen dioxide has properties more typical of an odd electron molecule. It is a coloured (brown), reactive gas which dimerises to the diamagnetic colourless gas dinitrogen tetroxide, N2O4. in which the odd electron is paired. The structure of dinitrogen tetroxide can be represented as a resonance hybrid of ... 

Consider the combination of nitric oxide and oxygen. Nitric oxide (a colorless gas) when mixed with oxygen gas (also colorless) becomes reddish-brown. The color is identical to that of another gas, nitrogen dioxide. All the properties of the nitric oxide-oxygen mixture are consistent with the conclusion that the gas nitrogen dioxide has... 

Nitrogen dioxide can be identified by color, odor, and physical properties. It is dissolved in warm water and converted to nitric acid. The latter may be measured by acid-base titration or from analysis of nitrate ion by nitrate ion-specific electrode or by ion chromatography. Alternatively, nitrogen dioxide may be passed over heated charcoal to produce nitrogen and carbon dioxide that may be analysed by GC-TCD or GC/MS (See Nitrogen, Analysis). The characteristic masses for N2 and CO2 formed for their identification are 28 and 44, respectively. 

Nitrogen tetroxide may be identified from physical and chemical properties and its ready conversion to NO2 gas which may be identified by its brown red color, pungent odor, and chemical analysis (See Nitrogen Dioxide, Analysis.)... 

A number of NO-derived reactive species can initiate lipid peroxidation, including nitrogen dioxide and, most notably, ONOO , which displays unique properties as a mediator of lipid oxidation. On a molecular basis, ONOO is a more potent lipid oxidant than hydrogen peroxide and, unlike H2O2, it does not require metal catalysis. The one-electron oxidants such as metals, as well as heme proteins and peroxynitrite, are assumed to play an important role in many diseases associated with oxidative stress. Heme proteins such as horseradish peroxidase (HRP) can produce alkylperoxyl radicals through two sequential... 

The acid-base properties of fused alkali nitrates were first noted when dichromate was added to fused sodium-potassium nitrate eutectic (/)/. Gaseous nitrogen dioxide and oxygen were slowly given off with the conversion of the dichromate to chromate. It was postulated that N02+ was formed as intermediate ... 

Properties.—The blue solution is unstable and decomposes slowly, with formation of sulphuric acid, sulphur dioxide and nitrogen dioxide. When shaken with air or submitted to oxidation by chlorine, nitric acid or hydrogen peroxide, conversion into nitrosulphonic acid is effected, brown fumes being liberated. Dilution -with water also destroys the coloured substance. If strongly cooled, the solution changes to an intense red, so that if a solution is too weak to possess a marked colour at the ordinary temperature, the presence of the purple acid can easily be detected by cooling in a mixture of acetone and solid carbon dioxide. 

Noteworthy properties were discovered in ammonium trichromate (NH4)3Cr3O10, produced while crystallizing ammonium bichromate from nitric acid, d = 1.39 (Siewert [47]). At 190°C the compound undergoes explosive decomposition, evolving nitric oxide and nitrogen dioxide. 

The very low value of Ashmore and Burnett is difficult to explain. It is easy to demonstrate that the discrepancy is not resolved by assuming the N03 intermediate in nitrogen dioxide decomposition is the pernitrite radical, in contradistinction to the symmetric nitrate radical. Their calculation of k5 depended on an experimentally obtained value for k 5 and an equilibrium constant K5- 5 calculated from thermodynamic properties for N03 measured by Schott and Davidson and Ray and Ogg. These results, obtained in a nitrogen pentoxide system, pertain to the nitrate radical, not the pernitrite radical. Guillory and Johnston176 reported an equilibrium constant based on estimated... 

Inorganic expl materials have also proven to he amenable to IR spectroscopic analysis. An IR spectrophotometric analysis method for carbon monoxide, carbon dioxide, nitric oxide, nitrous oxide and nitrogen dioxide produced in vacuum stability tests of expls stored together with polymeric materials has been developed (Ref 60). Structural properties, as elucidated by IR absorption, of a variety of new perfluorinated and halofluorinated covalent perchlorates are reported in Ref 42. Characterization of the products of the pyrot reaction of silicon and red lead in oxygen... 

Kenyon and coworkers17 much information concerning the preparation and properties of the product of oxidation of cellulose with nitrogen dioxide has been elaborated. This oxidation has been shown to occur with the initial rapid incorporation of nitrogen by the cellulose followed by a slower loss.174 This is interpreted as an initial nitration followed... 

When oxides of nitrogen come in contact with water, both nitrous and nitric acids are formed (18) (Table IV). Toxic reactions may result from pH decrease. Other toxic reactions may be a consequence of deamination reactions with amino acids and nucleic acid bases. Another consideration is the reactions of oxides of nitrogen with double bonds (Table IV). The cis-trans isomerization of oleic acid exposed to nitrous acid has been reported (19). Furthermore, the reaction of nitrogen dioxide with unsaturated compounds has resulted in the formation of both transient and stable free radical products (20, 21) (Table V). A further possibility has been raised in that nitrite can react with secondary amines to form nitrosamines which have carcinogenic properties (22). Thus, the possible modes of toxicity for oxides of nitrogen are numerous and are not exhausted by this short list. 

All pollutants can also cause deterioration of fiber properties. The effect of such pollutants as ozone, sulfur dioxide, and nitrogen dioxide on individual fibers is discussed later. 

---