Compressibility Factor Charts
The compressibility factor chart plots the compressibility factor Z, equal to PV/RT, where V is the volume per mole, versus the reduced pressure Pr for several values of the reduced temperature Tr. The reduced pressure and temperature are defined by
Pr = P/PC and Tr = T/TC, respectively, where PC is the critical pressure and TC is the critical temperature. Use buttons to select one of five molecules, and move the black dot to display the compressibility factor curve (blue) for any value of Tr between 1.0 and 1.8. The Z and Pr values for the location of the black dot are displayed on the chart. For an ideal gas, Z = 1 (green line).
view simulation and instructional video
This simulation was made at the University of Colorado Boulder, Department of Chemical and Biological Engineering.  Author(s): Rachael L. Baumann, Patrick Doyle
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