Lecture
This lecture discusses the concept of entropy, introduced historically during the study of steam engines, and its relation to the Carnot cycle. The entropy is defined as a state function independent of the transformation type. The Carnot cycle is shown to be optimal, decomposable into elementary Carnot cycles. The lecture also covers the relationship between entropy and reversible processes, emphasizing the extensive nature of entropy. The presentation concludes with the discussion of free energy and the minimization of free energy in spontaneous processes.