Dinitrogen tetroxide vapor

Estrogens Apply bands of sample solution, expose to ammonia vapor and dinitrogen tetroxide (from copper and cone, nitric acid), blow off excess and develop the nitroestrogens so formed. Detection by diazotization and coupling. [58]... 

A flask of volume 5.00 L is evacuated and 43.78 g of solid dinitrogen tetroxide, N,Q4, is introduced at — 196°C. The sample is then warmed to 25°C, during which time the N204 vaporizes and some of it dissociates to form brown NO, gas. The pressure slowly increases until it stabilizes at 2.96 atm. 

Dinitrogen tetroxide gas is produced by vaporizing dinitrogen tetroxide liquid. Dinitrogen tetroxide liquid boils at 21°C. If a small quantity is placed in a sealed flask at 100°C, it vaporizes, filling the flask with dinitrogen tetroxide gas. 

Nonmetal Oxides. Warm or molten white phosphorus burns vigorously in nitrogen oxide, dinitrogen tetroxide or pentoxide, and ignites in sulfur trioxide vapor or liquid.24... 

Vapor Sttate. Here the situation is much simpler. Ionic species are no longer present, and in the absence of nitric oxide the choice lies merely between nitrogen dioxide and dinitrogen tetroxide. The proportions vary very much with temperature at 21.15° C., the tetroxide is 15.9% dissociated, whereas dissociation to NO2 is complete at 140°. It does not necessarily follow, however, that reaction at low temperatures involves dinitrogen tetroxide, as reaction with olefins clearly shows. 

To obtain further evidence for the reaction scheme outlined above, the reaction has been carried out in the gas phase (7). Dimanganese decacarbonyl vapor and dinitrogen tetroxide were mixed at 60° C. A smoke was formed immediately the gases came into contact, which settled to a very pale yellow powder. This was the nitro compound, Mn(C0)5N02, containing only a trace of the nitrate, which may well have been formed by oxidation of the nitro compound under these conditions. The increased yield of Mn(C0)5N02 in the gas as compared with the liquid state is consistent with the free-radical interpretation, since heterolytic dissociation of the tetroxide is no longer possible. 

Iron Pentacarbonyl. In its reactions with liquid dinitrogen tetroxide this compound follows the pattern outlined above, and the remarks on reactions of nickel carbonyl probably apply here also. The solvate, Fe(N03)3.N204, is produced (4). This has the structure N0+[Fe(N03)4] in the solid state it is volatile without decomposition, and is believed to be a five-coordinate complex, Fe(N0)(N03)4, in the vapor state. We have not yet succeeded in isolating the simple trinitrate, Fe(N03)3, by removal of N2O4. 

The study of physical equilibrium yields useful information, such as the equilibrium vapor pressure (see Section 11.8). However, chemists are particularly interested in chemical equilibrium processes, such as the reversible reaction involving nitrogen dioxide (NO2) and dinitrogen tetroxide (N2O4) (Figure 14.1). The progress of the reaction... 

Combustible liquid (flash point 230°F/110°C cc). Ignites spontaneously in air. Sunlight causes rapid decomposition. Reacts with water or steam, producing toxic and flammable vapors. Violent reaction with strong oxidizers, dinitrogen tetroxide. Incompatible with strong acids, hydroxylamine. 

A reaction between hydrazine, N2H, and dinitrogen tetroxide, N20, has been used to launch rockets into space. The reaction produces nitrogen gas and water vapor. 

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