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### irreversible expansion of ideal gas

Posted: Sat Mar 14, 2020 6:16 pm
Why is w=0 for this? the example on p. 326 uses this to show that the entropy change of the surroundings is 0, which doesn't make a lot of sense to me on a conceptual level.

### Re: irreversible expansion of ideal gas

Posted: Sat Mar 14, 2020 6:45 pm
Looking at the example, it says free expansion. When something is said to freely expand, it means that the external pressure is 0. That means that w = -PV = 0.

### Re: irreversible expansion of ideal gas

Posted: Sat Mar 14, 2020 6:51 pm
Is W always zero for irreversible expansion?

### Re: irreversible expansion of ideal gas

Posted: Tue Mar 17, 2020 7:10 pm
From my understanding, free expansion is the same as a irreversible expansion which is when there is no external pressure on the system. If the system has no external pressure and if the gas is expanding against no external pressure, the gas is said to expand freely. Because there is no expansion against an external pressure, the expanding gas does no work, because work is equal to FD which is external force times distance traveled. No external force no work.