A Novel Sequence of Exposition of Engineering Thermodynamics*

We present the foundations of thermodynamics in a novel sequence in which all basic concepts are defined in terms of well known mechanical ideas. Many definitions are new. The order of introduction of concepts is: system (constituents and parameters); properties; state; energy (without heat and work) and energy balance; classification of states in terms of time evolution; existence of stable equilibrium states; available energy; entropy (without heat and temperature) of any state (equilibrium or not) and entropy balance; properties of stable equilibrium states; temperature in terms of energy and entropy; chemical potentials; pressure; work; heat; applications of balances. This novel sequence not only generalizes the subject of thermodynamics to all systems (large or small) and all states (equilibrium and not equilibrium) but also avoids both the conceptual and definitional difficulties that have been recognized by so many teachers, and the confusion experienced by so many students.