1. The problem statement, all variables and given/known data A pot is half filled with water and concealed by a lid so that no vapor can escape. The pot is then heated on a stove so steam is formed inside the pot. Now the heat is turned off and the vapor condenses into water. Explain when the process is reversible/irreversible. 3. The attempt at a solution From what I understand, they are asking about when the heating of the water is a reversible process, right? Okay, as far as I know the process is reversible if the entropy is the same before the heating and after the vapor has condensed. So if the pot is perfectly isolated the process is reversible. Otherwise it is not. Is this right?