The combined laws of Boyle and of Gay-Lussac give the familiar formula pv = nRT for the equation of state of any gas. No single gas, however, obeys this law exactly under all conditions. The classical experiment of Joule, moreover, seemed to show that the internal energy of a gas is independent of the volume, or (δU/δV)τ . More exact measurements subsequently performed by Joule and Thomsen established the fact that this conclusion is also inexact for all real gases, but that it is approached more closely the more a gas approaches the 'ideal state'. Deviations from these two laws are caused by the same phenomena, namely, the complexities of the force fields surrounding the molecules and other properties of the individual molecules composing the gas. It may be said that no real gas is ideal and that every gas approaches ideality as the pressure approaches zero or the volume approaches infinity.
Proceedings of the Iowa Academy of Science
©1939 Iowa Academy of Science, Inc.
Price, E. O.
"The Second Virial Coefficient as a Measure of Gas Imperfection,"
Proceedings of the Iowa Academy of Science, 46(1), 183-185.
Available at: https://scholarworks.uni.edu/pias/vol46/iss1/25