The Journal of Chemical Physics · 1938 · 257 citations · 5 references
Natural SciencesChemistryPhysicsCondensed Matter PhysicsPhysical ChemistryThermodynamicsChemical ThermodynamicsCondensationFree EnergyPhase TransitionsStatistical MechanicsStatistical ThermodynamicsCondensation ThermodynamicsCritical PointsCritical TemperatureGibbs Free EnergyGibbs Free Energy Of Phase ChangeThermodynamic Analysis
The Gibbs phase integral is generalized for chemically saturated molecules, yielding equations for their thermodynamic properties. The derived equations predict gas condensation into a condensed phase with surface tension below a characteristic temperature Tm, zero surface tension at Tm with a discontinuous transition without heat, a finite volume interval of constant pressure and Gibbs free energy between Tm and the critical temperature Tc, and above Tc a conventional P–V diagram with no volume where (∂P/∂V)T = 0.
A general development of the Gibbs phase integral for a system of chemically saturated molecules gives equations for the thermodynamic properties of the system. The equations predict the usual condensation phenomenon of the gas to form a condensed phase with a surface tension at temperatures below a characteristic temperature Tm. At Tm the surface tension of the condensed phase is zero, and this phase undergoes a discontinuous change without heat of transition. Between Tm and the true critical temperature Tc, there exists a finite volume interval for which P and the Gibbs free energy F is independent of the volume. Above Tc the usual P—V diagram predicted above the critical point is found, with no volume for which (∂P/∂V)T is zero.
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