Nitrogen liquid, vapor pressure

Isophorone dllsocyanate (CAS 4098-71-9]) Based on animal studies, extremely Irritating upon direct contact severe burns may result. By analogy with other Isooyanates, vapors or mists likely to be potent respiratory sensitizers, oausing asthma. See also p 232. 0.005 ppm 2 2 W 1 Coloriess to pale yellow liquid. Vapor pressure Is 0.0003 mm Hg at 20°C (68°F). Possible thermal-breakdown products include oxides of nitrogen and hydrogen cyanide. 

Nltropropane (CAS 79-46-9) Mildly irntatlng CNS depressant at high exposures. Highly hepatotoxic fatalities have resulted. Renal toxicity also occurs. Well absorbed by all routes. Limited evidence for adverse effects on fetal development in test animals. A carcinogen in test animals (lARC 2B). 10 ppm, A3 NIOSH CA 100 ppm 1 3 2 (may explode on heating) Coloriess liquid. Vapor pressure is 12.9 mm Hg at 20°C (68°F). Flammable. Thermal-breakdown products include oxides of nitrogen. 

Smaller quantities of liquid nitrogen are shipped in liquid cylinders, which are pressurized stainless steel vacuum-insulated containers with capacities of 160—180 L of hquid nitrogen, producing 100—120 (3800—4600 SCF) gaseous nitrogen when vaporized. Moderate quantities of high pressure gaseous... 

If we raise the temperature still further, the liquid vaporizes to form nitrogen gas, taking whatever density is necessary to fill the container. The density now depends upon the volume of the container and the temperature. For the sake of comparison, suppose the gaseous nitrogen is placed in that volume that gives a pressure of one atmosphere when the container is placed in an ice bath at 0°C. Then the density is found to be only 0.00125 gram per milliliter. This means that the volume required for one mole of gas is... 

A cylinder contains nitrogen gas and a small amount of liquid water at a temperature of 25°C (the vapor pressure of water at 25°C is 23.8 mm). The total pressure is 600.0 mm Hg. A piston is pushed into the cylinder until the volume is halved. What is the final total pressure ... 

Colorless, odorless and tasteless gas diamagnetic density 1.229 g/L converts to a colorless liquid at -195.79°C specific gravity of the hquid N2 0.808 solidifies at -210 C solid nitrogen exists in two allotropic forms, a cubic alpha form and a hexagonal beta form alpha allotrope changes to beta form at -237.5°C critical temperature -146.94°C critical pressure 33.46 atm vapor pressure of the fluid at -203°C 5.1 torr the gas is slightly soluble in water, 2.4... 

H(a)-TaS2 powder (1.91 g about 0.008 mole) is placed in a Pyrex tube about 20 cm long and 1 cm in diameter, with a 2-mm wall thickness. An excess of redistilled pyridine is then added. The volume of pyridine should be three or four times that of the TaS2 powder. ("Caution. Direct contact with pyridine or pyridine vapor should be avoided.) The tube is connected to avacuum system and is quickly pumped down to 15 torr pressure (vapor pressure of liquid pyridine at room temperature). The pyridine is then frozen with liquid nitrogen, and the evacuation is continued to a pressure of 10 3 torr. To remove dissolved air,... 

Argon at liquid-nitrogen temperature exhibits an equilibrium pressure of 187 torrs. It offers the advantage of a lower vapor pressure than nitrogen, which will reduce the void volume error while retaining ease of pressure measurements. However, the cross-sectional area of argon is not well established and appears to vary according to the surface on which it is adsorbed. 

Homogeneous Liquids. The physical properties important in determining the suitability of a liquid for propellant application are the freezing point, vapor pressure, density, and viscosity. To a lesser extent, other physical properties are important such as the critical temperature and pressure, thermal conductivity, ability to dissolve nitrogen or helium (since gas pressurization is frequently used to expel propellants) and electrical conductivity. Also required are certain thermodynamic properties such as the heat of formation and the heat capacity of the material. The heat of formation is required for performing theoretical calculations on the candidate, and the heat capacity is desired for calculations related to regenerative cooling needs. 

Following the reaction, the borazine collected in the liquid-nitrogen traps (I) is further purified by a single vacuum fractionation,9 as shown in Figure 2, through a U-trap series cooled at — 45°C (A), — 78°C (B), and — 196°C (C). In the — 78°C trap (B), 13.1 g (0.16 mol, 60% yield based on starting BH4) of borazine is condensed. No other products are detected in the IR, nB NMR, H NMR (see below), or GC/MS spectra of the product, and its vapor pressure (85 Torr at 0°C) matches the literature value,10 indicating that the borazine is obtained in excellent purity. 

Cryostats described elsewhere (14) were used between 123° and 273°K. Temperature control was within 0.1°C and temperature was read using appropriate vapor-pressure thermometers. For still lower temperatures liquid nitrogen and liquid oxygen were used. 

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