Chapter 6: The Second Law of Thermodynamics

In the last two chapters of this book we applied the first law of thermodynamics to closed and open systems considering both quasistatic and non-quasi-static processes. A question that arises naturally is whether all processes that satisfy the first law could be carried out in practice. In order to explore this question we need to introduce the second law of thermodynamics which teaches us that there are additional conditions for the feasibility of a process. In particular, the irreversibility of natural processes is an important consequence of the second law.