The State Principle—Some General Aspects of the Relationships Among the Properties of Systems

Abstract

Abstract An independent generalization, here called the “State Principle,” is necessary for the development of thermodynamics. Previously, this principle has been either tacitly assumed, or at best stated incompletely. A discussion and explicit formulation of this principle are given. The Phase rule is deduced from the State Principle and certain related empirical information. In this derivation no reference whatsoever is made to the First Law or the Second Law of Thermodynamics. A new, simple, systematic means for counting the number of components in the phase rule, which has no known exceptions and which does not rely on either advanced thermodynamics or the First and Second Laws, is presented. Examples of its use are included.