This applet models the isotherms for the non-ideal gas, using the Virial Equation to third order. Isotherms are traces of the relationship between the volume and the pressure at a constant temperature.
The Virial Equation to third order is p = RTV -1 {1 + B(T)V -1 + C(T)V -2 + D(T)V -3}, where V is the molar volume, p is the pressure, T is the temperature, and B(T), C(T) and D(T) are constants specific to a particular gas (and are dependent on the particular temperature). One can think of the perfect gas law as the virial equation to zeroth order.
Click on T+ to increase the temperature, and T- to decrease it. Likewise, click on B+ to increase the parameter B(T), and B- to decrease it. Click on C+ to increase the parameter C(T), and C- to decrease it. The units of B are L mol -1, the units of C are L 2 mol -2, and the units of D are L 3 mol -3.
© 2004-2011 by Lawrence T. Sein. All rights reserved.
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