VAPOR PRESSURES OF LIQUID OXYGEN BETWEEN TRIPLE POINT AND CRITICAL POINT

Vapor pressure measurements reported in the literature for liquid oxygen have been subjected to a rigorous analysis to establish the constants of the Frost-Kalfwarf vapor pressure equation. This investigation has considered all pertinent measurements reported since 1884 and includes in excess of 423 values. A screening procedure reduced this number to 259 reliable points which have served to define the constants of this vapor pressure equation as follows:[formula omited] where P is millimeters of mercury and T is the temperature in 0 K. This relationship covers the range included between the triple point and critical point and has the capability to reproduce the more accurate experimental measurements with an average deviation of 0.43%. The triple point, Tt = 54.363° K., Pt = 1.125 mm. of Hg and the critical point, Tc = 154.33° K., Pc = 49.713 atm. were deduced from the analysis of these data. © 1968, American Chemical Society. All rights reserved.