Need Help Solving for Work Done: 60,000 J

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The discussion revolves around calculating the work done in a thermodynamic process, with the correct answer being 60,000 J. The initial calculations presented include work done during gas compression and expansion, but the figures do not align with the expected result. Key points include the need to use average pressure for calculations and the importance of unit conversions, specifically using L-atm to J. Adjusting the pressure value to 3.5 atm brings the calculations closer to the correct answer. The conversation highlights the significance of proper unit handling and pressure averaging in thermodynamic work calculations.
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All, I need some direction on the following question, please.
Correct answer is 60,000 J according to book.

Here's what I have so far, but it may be incorrect: Work done C-->D is (2 atm)(-400 L)(101) = -81,000 J, so work was done on the system when the gas was compressed. No work is done D-->A. Lastly, work done A-->C is (3 atm)(400 L)(101) = 121,200 J. This is work done by the gas on the surroundings. As you can see, my figures do not get to 60,000 J! Thanks in advance. Hopefully I haven't done anything too stupidly obvious!
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For A-->C, why did you use 3atm? Shouldn't it be the average pressure?
 
units for pressure should be Pa and units for volume should be m3
 
The conversion was handled with the (101) term.
1 L-atm = 101.325 J
Perhaps the problem assumes a simpler conversion factor of approx. 1:100.
 
Yes, it should be 3.5 atm and this gets me very close to the 60,000 J answer. Thank you.
 
RUber said:
The conversion was handled with the (101) term.
1 L-atm = 101.325 J
Perhaps the problem assumes a simpler conversion factor of approx. 1:100.
RUber said:
The conversion was handled with the (101) term.
1 L-atm = 101.325 J
Perhaps the problem assumes a simpler conversion factor of approx. 1:100.

sorry...I see that the units were taken care of 103 x 10-3
 
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