# van der Waals' equation

### or van der Waals equation

[van der wahlz, wawlz; Dutch vahn duh r vahls]

- an equation of state relating the pressure, volume, and absolute temperature of a gas, taking into account the finite size of the molecules and the attractive force between them.

## Origin of van der Waals' equation^{}

named after J. D. van der Waals (1837–1923), Dutch scientist

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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

# van der Waals equation

- an equation of state for a non-ideal gas that takes account of intermolecular forces and the volume occupied by the molecules of the gas

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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# van der Waals equation

- An equation that relates the pressure, volume, and absolute temperature of a gas taking into account the finite size of molecules, and their intermolecular attraction, having the form RT = (P + av-2)(v - b), where R is the gas constant, T is the absolute temperature, P is the pressure, v is the volume of fluid per molecule, a is a measure of the attraction of the molecules for each other (due to van der Waals forces), and b is the volume occupied by a single molecule. The equation accurately captures phase transitions between liquid and gas phases of substances. See also ideal gas law.

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