Hydrogen atmosphere 800 atomic weight

The elements whose isotopes are routinely measured with gas inlet mass spectrometers are carbon (12C and 13C, but not 14C), oxygen (160, 170, l80), hydrogen ( H, 2H, but not 3H), nitrogen (14N and 1SN) and sulphur (32S, 33S, 34). Stable isotopes of H, C, N, O, and S occur naturally throughout atmosphere, hydrosphere, lithosphere, and biosphere. They are atoms of the same elements with a different mass. Each element has a dominant light isotope with the nominal atomic weight (I2C, 160,14N, 32S, and H) and one or two heavy isotopes (l3C, nO, 180, 15N, 33S, 34S, and, 2H) with a natural abundance of a few percent or less Table 1). 

White, Friedman, and Johnston (343) have measured the critical constants for normal hydrogen and have found 33.244 K. and 12.797 atmospheres. Woolley, Scott, and Brickwedde have presented data on the dissociation energy and the thermodynamic properties for the ideal diatomic gas, including contributions from nuclear spin. We have omitted the spin entropy in compiling our tables. Thermodynamic properties for the ideal monatomic gas have been computed at the National Bureau of Standards (395). Note that the reference state represents 2 gram atomic weights for this element. 

Figures 9 and 10 show yields of major products as functions of severity, here measured by the CH4/C3H0 molar ratio. Both time and temperature were varied to vary severity. For comparison we show yields by conventional cracking at about 1/1 by weight steam dilution, the yields shown were obtained by cracking a feedstock with a hydrogen/carbon atom ratio (H/C) of 1.89. This would correspond to a light mid-east crude oil, hydrogenated to reduce sulfur, or to a wide range distillate (naphtha through vacuum gas oil) from the same crude or to an atmospheric gas oil from one of these crudes. Since crude oils cannot be cracked in conventional plant furnaces, the data shown correspond to a high-quality atmospheric gas oil.

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