Compressed gases vapor density

A key limitation of sizing Eq. (8-109) is the limitation to incompressible flmds. For gases and vapors, density is dependent on pressure. For convenience, compressible fluids are often assumed to follow the ideal-gas-law model. Deviations from ideal behavior are corrected for, to first order, with nommity values of compressibihty factor Z. (See Sec. 2, Thvsical and Chemical Data, for definitions and data for common fluids.) For compressible fluids... 

Colorless gas pungent suffocating odor human odor perception 0.5 mg/m hquefies by compression at 9.8 atm at 25°C, or without compression at -33.35°C (at 1 atm) sohdifies at -77.7°C critical temperature and pressure, 133°C and 112.5 atm, respectively vapor density 0.59 (air l) density of liquid ammonia 0.677 g/mL at —34°C dielectric constant at —34°C is about 22 extremely soluble in water solution alkaline pKa 9.25 in dilute aqueous solution at 25°C the gas does not support ordinary combustion, but bums with a yellow flame when mixed in air at 16— 27% composition. 

Gases Gases/vapors are compressible and their densities are strong functions of both temperature and pressure. Equations of state (EoS) are commonly used to correlate molar densities or molar volumes. The most accurate EoS are those developed for specific fluids with parameters regressed from all available data for that fluid. Super EoS are available (or some of the most industrially important gases and may contain 50 or more constants specific to that chemical. Different predictive methods may be used for gas densities depending upon the conditions ... 

Xenon, Xe, is a gaseous, nonmetallic element from family eight. It is a colorless, odorless gas or liquid. It is nonflammable and nontoxic at standard temperatnres and pressnres, but is an asphyxiant and will displace oxygen in the air. The boiling point is -162°F, and the vapor density is 05.987, which is heavier than air. Xenon is chemically unreactive however, it is not completely inert. The fonr-digit UN identification number is 2036 for the compressed gas and 2591 for the cryogenic liqnid. Xenon is used in luminescent tubes, flash lamps in photography, lasers, and as an anesthesia. 

A compressed gas with a vapor density greater then 1 will have what relationship with air ... 

The gas-phase density is the reciprocal of the molar volume, pv = 1/K, and hence can be estimated from any equation of state, for example, the Redlich-Kwong equation (1949), Kunte and Doraiswamy s (1958) plots of reduced density as a function of P, and provide a quick and reasonably accurate method of estimating vapor density. From our point of view, the most useful are the charts developed by Nelson and Obert (1954) in which the compressibility factor Z defined as Z = PV/R T is plotted as a function of P for various values of based on experimental data for a number of compounds. Then the density may be calculated from... 

Boiling point, -166 Melting point, -169 Relative vapor density (air 1) 1.38 Solubility in water none Relative atomic mass 39.9 LogPoctanol/water 0.9 Grossformula Ar COLORLESS, ODORLESS COMPRESSED QAS Gas is heavier than air and can accumuiate ciose to ground level, causing oxygen deficiency, with risk of unconsciousness. ... 

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