Which answer below is not a statement of the second law of thermodynamics?
A) Real processes proceed in a preferred direction.
B) Energy does not flow spontaneously by heat from a cold to a hot reservoir.
C) The entropy of the universe increases in all natural processes.
D) In theory, heat engines working in a cycle employ reversible processes.
E) You cannot construct a heat engine, operating in a cycle that does nothing but take heat from a reservoir and perform an equal amount of work.

Question

Quizplus · Accepted Answer

D is not a statement of the second law of thermodynamics. It is a statement about the theoretical possibility of heat engines employing reversible processes, which is related to the concept of the Carnot cycle but not to the second law itself. The other choices all relate to the second law in specific ways. A describes the irreversibility of real processes, B describes the direction of energy flow, C describes the increase in entropy, and E describes the impossibility of a hypothetical type of heat engine.

Which Answer Below Is Not a Statement of the Second