Nitric Acid and Nitrogen Oxides

Oxidations with nitric acid under the best conditions convert primary alcoholic and aldehydic groups to carboxylic groups. Frequently, however, cleavage of carbon-carbon bonds occurs. For galactose the conversion to insoluble mucic acid, COOH—(CHOH)4—COOH, takes place to an extent greater than 70 %, and the reaction is used for the quantitative determination of this sugar (229, 230). This oxidation has been halted before completion and a 10% yield of the L-galacturonic acid obtained (231). Smaller 

Oxidation of methylated sugars with nitric acid has been used extensively for the purpose of demonstrating the position of unsubstituted hydroxyl groups. (See under Structure of glycosides and sugars such as maltose, sucrose, etc.) 

Cleavage of carbon-carbon bonds appears to be facilitated by the presence of catalysts such as vanadium salts, and tartaric and oxalic acids are formed in good yields at the expense of saccharic acids (233). Since hot nitric acid acts as a hydrolyzing agent as well as an oxidizing agent, oligo- and polysaccharides may be used. 

Kiliani (234) has made an extensive study of the nitric acid oxidations of 

Browne and F. W. Zerban, Sugar Analysis, pp. 691, 728. Wiley, New York, 1941 A. W. van der Haar, Monosaccharide and Aldehydsauren, Born-traeger, Berlin, 1920. 

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An excellent review of the composition of MA, nitric acid and nitrogen oxides is given by Urbanski (Ref 74, pp 12-52, 102-04)... 

Nitric acid and nitrogen oxides are driven off together with water vapour and pass from the tower through the top to a Bleacher (3) filled with disks or cylinders where they pass in counter-current to the condensed acid which returns from the S-bend condenser (4) of high-silicon iron to flow through (5) to storage. 

H.16 The first stage in the production of nitric acid by the Ostwald process is the reaction of ammonia with oxygen, producing nitric oxide, NO, and water. The nitric oxide further reacts with oxygen to produce nitrogen dioxide, which, when dissolved in water, produces nitric acid and nitrogen oxide. Write the three balanced equations that lead to the production of nitric acid. 

Synonyms nitrogen peroxide Formula N02 MW 46.01 CAS [10102-44-0] occurs in the exhausts of automobiles and in cigarette smoke produced by the reaction of nitric acid with metals and decomposition of nitrates or during fire reddish-brown fuming liquid or gas sharp pungent odor liquefies at 21°C solidifies at -9.3°C density of liquid 1.45 at 20°C vapor 1.58 (air= 1) reacts with water to form nitric acid and nitrogen oxide reacts with alkalies to form nitrates and nitrites highly toxic. 

Lignocellulosic Materials Nitric Acid and Nitrogen Oxides", Ph.D. Thesis, University of California, Berkeley, 1973. 

Nitration offers a method of making unreactive paraffins into reactive substances without cracking. Because nitric acid and nitrogen oxides are strong oxidizing agents, oxidation always accompanies nitration. Aromatic nitration reactions have been important particularly for the manufacture of explosives. Nitrobenzene is probably the most important nitration product. 

At the beginning of acidification a temperature of 25°C should be maintained. During the addition of the first 4000 kg of acid the temperature is allowed to rise up to 35°C. On adding a further 2500 kg of acid the temperature rises up to 60°C. Then the whole is mixed for an hour at 70°C. After cooling, the layer of nitro compound is separated from that of the acid. The spent acid is shaken with benzene to remove any nitrobenzene, nitric acid and nitrogen oxides that may be left. Then the spent acid is transferred to a distillation plant, where it is subjected to concentration up to 70% of H2S04. The benzene from the extraction is either recycled to the nitration plant or is distilled off to separate it from nitrobenzene. 

Three studies of one mining population were located that equivocally associated reproductive effects in humans following inhalation exposure to uranium. The studies reported that male uranium miners were found to have more first-born female children than expected, suggesting that uranium s alpha radiation damaged the y-chromosomes of the miners (Muller et al. 1967 Waxweiler et al. 1981b Wiese 1981). In addition, it is not certain if the effect described is from exposure to uranium because the workers were also exposed to Rn, chlorine, hydrofluoric acid, lead sulfate, nickel, nitric acid and nitrogen oxides, silicon dioxide, and sulfuric acid (Dupree et al. 1987). 

The four kinds of active carbons used in our laboratory were obtained from different commercial sources and in accordance with supplier information were produced from various precursors. Ash was removed from the raw carbon using concentrated hydrofluoric and hydrochloric acids by Korver s method [166]. Carbon samples were subjected to surface modification by oxidation in air or with concentrated HNO, annealing in a vacuum or an ammonia atmosphere. Afterwards, all carbon samples were desorbed under vacuum (10" Pa) at 150°C (423 K) for 3 h. The procedure used for carhon purification ensured the removal of nitric acid and nitrogen oxides (after nitric acid oxidative modification) or physically sorbed NHi (after heat treatment in ammonia). The samples thus prepared... 

Nitrogen dioxide is a choking, poisonous, brown gas that contributes to the color and odor of smog. The oxidation number of nitrogen in NO2 is-1-4. NO2, like NO, is paramagnetic. It disproportionates in water to form nitric acid and nitrogen oxide ... 

Joseph, D. W., and C. W. Spicer (1978). Chemiluminescence method for atmospheric monitoring of nitric acid and nitrogen oxides. Anal. Chem. 50, 1400-1403. 

Nitric acid and nitrogen oxides are assuming new significance as oxidizing agents. Toluic acids may be made by the nitric acid oxidation of xylenes p-toluic acid is obtained from oxidation of p-cymene through the oxidation of the isopropyl group. Nitric acid in the presence of sulfuric acid and a... 

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