Thermodynamics. Using Affinities to define reversible processes

TL;DR

This paper proposes a new thermodynamic definition of reversible processes based on affinities, which avoids the circularity of entropy-based definitions and is demonstrated with practical examples.

Contribution

It introduces a novel affinity-based definition of reversible processes that precedes entropy concepts, enhancing conceptual clarity in thermodynamics.

Findings

Defines reversible processes using affinities

Avoids circularity in entropy definitions

Demonstrates advantages with examples

Abstract

In this article a definition of reversible processes in terms of differences in intensive Thermodynamics properties (Affinities) is proposed. This definition makes it possible to both define reversible processes before introducing the concept of entropy and avoid the circularity problem that follows from the Clausius definition of entropy changes. The convenience of this new definition compared to those commonly found in textbooks is demonstrated with examples.