Chemical thermodynamics in Landsberg’s formulation

Scientific article / Proc. Roy. Soc. Lond. A, 1970, v. 317, p. 477–510.A presentation is given of the form taken by the thermodynamic theory of homogeneous chemical equilibrium when transcribed into Landsberg’s (1961) formulation of thermodynamics in terms of set theory.Certain sets of points can usefully be defined, in order to deal separately and explicitly with metastable equilibrium states, and with open systems as such, without having simultaneously to consider non-equilibrium states. ‘Narrower’ and ‘wider’ thermodynamic principles can be distinguished in terms of what is the set for which some proposition is asserted to apply, and Landsberg’s formulation makes possible greater clarity in the enunciation of the special axioms of chemical thermodynamics. In particular, the axiom of the ideal behaviour of dilute systems takes a very clear-cut significance.When arguments of the type introduced by Landsberg are used, the assumptions involved in a formal development of the thermodynamic theory of homogeneous chemical equilibrium are clearly apparent. Metastable equilibrium states, and non-equilibrium states, each have their own distinct place in the theory.Some comments are made in relation to the usual presentation.