When is the Heating of a Pot of Water Reversible?

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SUMMARY

The discussion centers on the reversibility of heating water in a pot, specifically when steam forms and subsequently condenses back into water. The process is reversible if the system is perfectly isolated, maintaining the same entropy before and after heating. The input of work is not required to return to the initial state, reinforcing the argument for reversibility. Insulation of the pot during heating does not affect this conclusion, and the initial temperature of the water does not need to be 100°C for the process to be reversible.

PREREQUISITES
  • Understanding of thermodynamics, particularly the concepts of entropy and reversible processes.
  • Familiarity with the properties of water and phase changes (liquid to vapor and vice versa).
  • Knowledge of isolated systems in thermodynamic contexts.
  • Basic principles of heat transfer and insulation effects.
NEXT STEPS
  • Research the laws of thermodynamics, focusing on entropy and reversibility.
  • Study phase transitions of water, including boiling and condensation processes.
  • Explore the concept of isolated systems and their implications in thermodynamic processes.
  • Investigate the effects of insulation on heat transfer and system behavior.
USEFUL FOR

Students studying thermodynamics, educators teaching physics concepts, and anyone interested in the principles of heat transfer and phase changes in water.

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Homework Statement



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.

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?
 
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Does it require the input of work to return from point 2 back to point 1? In this case, NO so you have a very good argument for it being reversible.
 
Does it matter if the pot is insulated during the heating? I'd say no.

What if for example the water starts at 20C, and then heated until some steam is formed. Will it then be reversible? Or must it begin at 100C?
 

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