Thermodynamic Problems: Work and Heat in a Thermodynamic Process

AI Thread Summary
The discussion revolves around calculating the work associated with a thermodynamic process involving an ideal gas. The gas undergoes cooling at constant volume and then expands at constant pressure, with initial and final states provided. The participant attempts to calculate work using the formula W = -P * deltaV but faces issues with significant figures and clarity on the sign convention. There is a consensus that while the method is correct, attention to detail in units and context is crucial for accurate results. The conversation emphasizes the importance of precision in thermodynamic calculations.
yuvlevental
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Homework Statement


Initially, 0.745 moles of an ideal gas in a container occupies a volume of 3.55 L at a pressure of 3.82 atm with an internal energy of 1705 J. The gas is then cooled at a constant volume until its pressure is 2.06 atm. Then the gas is allowed to expand at a constant pressure until its volume is 6.65 L. The final internal energy is 2098 J. Consider the processes to be quasi-static. What is the work associated with this entire process?

Homework Equations


W=-P*deltaV
deltaU=Q + W

The Attempt at a Solution


Is it correct that you take the 2.06, multiply it by 1E5, and multiply the answer by the change in volume in m^3 to find -638.60 J
 
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Yes and no. Your method is correct, but your answer has too many sig figs.
 
yuvlevental said:
What is the work associated with this entire process?
Other than sig figs, the use of prepositions matters. Work done on what by what? I think that there is a sign uncertainty here.
 

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