REMARKS ON THE CLASSICAL-THEORY OF CAPILLARITY

The present paper describes a new way of presentation of the classical theory of capillarity. An approach based on the Omega-potential therm odynamic formalism is used. An explicit definition of the Gibbs excess quantities of the extensive thermodynamic functions is proposed. It i s emphasized that the Omega-potential is the only extensive thermodyna mic function which, when defined as an excess quantity, is not in fact such a quantity. It holds for the case of two-phase plane-interface e quilibrium systems. The work of transformation of a homogeneous system into a heterogeneous one at given conditions, (Delta Omega)(T,V,ui), is defined by means of Eq.(39). Different capillary systems and differ ent thermodynamic models for their description can be unified on the b asis of Eq.(39).