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### HW 8.11 part b

Posted: Thu Jan 31, 2019 2:16 pm
A piston confines 0.200 mol Ne(g) in 1.20 L at 25 C. Two experiments are performed. (a) The gas is allowed to expand through an additional 1.20 L against a constant pressure of 1.00 atm. (b) The gas is allowed to expand reversibly and isothermally to the same final volume. Which process does more work?

For this question, could someone help me understand why would the second experiment does more work?

### Re: HW 8.11 part b

Posted: Thu Jan 31, 2019 2:56 pm
The second experiment does more work because all energy is going into moving the piston (none is going into increasing the temperature because the experiment is an isothermic expansion). You can determine this quantitatively by calculating the work done by the first experiment using the equation w=P(V2-V1) and calculating the work done by the second experiment with the equation w=nRTln(V2/V1).

### Re: HW 8.11 part b

Posted: Fri Feb 01, 2019 10:16 am
For the change in volume (V2-V1) is it 2.4-1.2 or 1.2-1.2?
What values do you get for part a and part b?

ThomasLai1D wrote:The second experiment does more work because all energy is going into moving the piston (none is going into increasing the temperature because the experiment is an isothermic expansion). You can determine this quantitatively by calculating the work done by the first experiment using the equation w=P(V2-V1) and calculating the work done by the second experiment with the equation w=nRTln(V2/V1).