.Calculating Heat Released from Gas Expansion at Constant Temperature

AI Thread Summary
The discussion revolves around calculating the heat released from an ideal gas during an isothermal expansion and subsequent return to its original state. The gas is heated to a temperature of 2To and then expands at this temperature before returning to the initial conditions at To. It is clarified that the internal energy increases by 3PoVo/2 during the process from point B to To, but since the temperature remains constant during the expansion, the change in internal energy is zero. Consequently, no heat is released or absorbed, leading to the conclusion that the correct answer is 0. The key takeaway is that in isothermal processes, the internal energy does not change with temperature, resulting in no heat transfer.
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An ideal gas at pressure, volume, and temp, Po, Vo, and To, respectively, is heated to point A, allowed to expand to point B also at A's temperature 2To, and then returned to the original condition. The internal energy increases by 3PoVo/2 going from point B to point To. How much heat left the gas from point B to point To?

a. 0 b. PoVo/2 c. 3PoVo/2 d. 5PoVo/2

http://www.msu.edu/~kossakze/pvt.gif

Not sure about this one. Any suggestions? Thanks
 
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Can't understand how internal energy increases if the temp. changes from 2T0 to T0??
 


The correct answer is a. 0. This is because the process described is an isothermal expansion, meaning the temperature remains constant throughout. In an isothermal process, the change in internal energy is equal to 0, so no heat would be released or absorbed by the gas. The internal energy only increases when the temperature changes, which does not occur in this scenario. Therefore, the correct answer is 0.
 

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