Odor of nitrogen dioxide

When eonfmed in the elosed cell and subjected to the isothermal storage test performed at a T, of 76.97 °C, i.e., a temperature a little lower than the SADT calculated herein, 0.4 g of eollodion cotton started the autocatalytic reaction, though faintly, about 7.42 d after the start of the isothermal storage test. The sample was found to be yellow and gave off the odor of nitrogen dioxide after the test the inside of the cell was found to be pressurized besides. 

The sample was found to be pale yellow and gave off the odor of nitrogen dioxide after the test the inside of the cell was found to be pressurized besides. 

PHYSICAL PROPERTIES yellowish-brown liquid or reddish-brown gas (above 70°F) in solid form (below 15°F) may appear as white to bluish-white snow pungent, irritating odor soluble in concentrated sulfuric acid and nitric acids soluble in alkalies, chloroform, and carbon disulfide commercial brown liquid under pressure is an equilibrium mixture of nitrogen dioxide and the colorless N2O4 MP (-9°C, 15°F) BP (21°C, 70°F) DN (1.448 g/mL liquid at 20°C) LSG (1.44 at 68°F) HV (9.110 kcal/mol) VD (1.58) VP (400 mmHg at 80 C) OT (4 ppm). 

Reddish-brown gas with an acrid, pungent odor liquefies under pressure to a brown fuming liquid, which is a mixture of nitrogen dioxide and colorless nitrogen tetroxide, N2O4 density of gas 1.58 (air = 1), liquid 1.448 at 20°C (68°F) 1 L of gas weighs 3.3 g at 21°C (69.8°F) liquefies at 21°C (69.8°F), solidifies at -9.3°C (15.26°F) reacts with water to form nitric acid and nitric oxide, reacts with alkalies to form nitrates and nitrites soluble in nitric and sulfuric acids. 

The characteristic pungent odor of ozone is noticeable in the vicinity of electrical machines and power transmission lines. Ozone is formed in the atmosphere during electrical storms and by the photochemical action of ultraviolet radiation on a mixture of nitrogen dioxide and 0 q gen. Areas with high air pollution are subject to high atmospheric ozone concentrations. 

Nitrogen dioxide, N02 (oxidation number -t-4), is a choking, poisonous, brown gas that contributes to the color and odor of smog. The molecule has an odd number of electrons, and in the gas phase it exists in equilibrium with its colorless dimer N204. Only the dimer exists in the solid, and so the brown gas condenses to a colorless solid. When it dissolves in water, NOz disproportionates into nitric acid (oxidation number +5) and nitrogen oxide (oxidation number +2) ... 

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 dioxide is a red-brown gas that is very soluble in water. It has an unpleasant odor and is quite poisonous. When nitrogen dioxide is cooled, its brown color fades to a pale yellow. Molecular weight determinations show that this yellow substance has a formula of N2O4 (nitrogen tetroxide) ... 

Unlike nitrous oxide and nitric oxide, nitrogen dioxide is a highly toxic yellow-brown gas with a choking odor. In the laboratory nitrogen dioxide is prepared by the action of concentrated nitric acid on copper (Figure 21.7) ... 

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