What is the defining feature of a thermodynamic process?

The defining feature of a thermodynamic process is a series of continuous states followed by a working substance. In thermodynamics, a process refers to the path taken by a system as it moves from one thermodynamic equilibrium state to another. This involves changes in properties such as temperature, pressure, and volume.

In this context, the working substance (often a gas) undergoes transformations that can be described through a sequence of states defined by these properties. The process can be isothermal (constant temperature), adiabatic (no heat exchange), isobaric (constant pressure), or isochoric (constant volume), each illustrating how the system’s state changes under different conditions.

Understanding that a thermodynamic process highlights the transition between states is crucial, as it allows for the application of laws and concepts such as the first and second laws of thermodynamics. These principles drive the behavior of energy interactions and help predict the outcomes of thermal systems, making the concept of continuous states essential in thermodynamics.