The compressibility factor chart plots the compressibility factor \(Z\), equal to \(\frac{PV}{RT}\), where \(V\) is the volume per mole, versus the reduced pressure \(P_r\) for several values of the reduced temperature \(T_r\). The reduced pressure and temperature are defined by \(P_r = P/P_c\) and \(T_r = T/T_c\), respectively where \(P_c\) is the critical pressure and \(T_c\) 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 \(T_r\) between 1.0 and 1.8. The \(Z\) and \(P_r\) values for the location of the black dot are displayed on the chart. For an ideal gas, \(Z\) = 1 (green line).

This simulation was created in the Department of Chemical and Biological Engineering, at University of Colorado Boulder for LearnChemE.com by Rachael Baumann under the direction of Professor John L. Falconer and was converted to HTML5 by Patrick Doyle, with additional contributions by Neil Hendren. This simulation was prepared with financial support from the National Science Foundation. Address any questions or comments to learncheme@gmail.com. All of our simulations are open source, and are available on our LearnChemE Github repository.

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