A system goes from state 1 to state 2 and back to state 1.
(a) What is the relationship between the value of ?E for going from state 1 to state 2 to that for going from state 2 back to state 1?
(b) Without further information, can you conclude anything about the amount of heat transferred to the system as it goes from state 1 to state 2 as compared to that upon going from state 2 back to state 1?
(c) Suppose the changes in state are reversible processes. Can you conclude anything about the work done by the system upon going from state 1 to state 2 as compared to that upon going from state 2 back to state 1?