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How about the change in the internal energy of a substance when it is condensed from saturated vapour to saturated liquid isothermally?

Sincerely thanks to those who help me :)

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- #1

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How about the change in the internal energy of a substance when it is condensed from saturated vapour to saturated liquid isothermally?

Sincerely thanks to those who help me :)

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Chestermiller

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Yes.Hi all, I was taught that internal energy of an ideal gas in depending on the temperature which mean during isothermal process, the change in internal energy is equal to zero. Is this statement true?

No. During the condensation, it is not an ideal gas. It's part vapor and part liquid.How about the change in the internal energy of a substance when it is condensed from saturated vapour to saturated liquid isothermally?

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That's true for an ideal gas, but in real gases there's a slight dependence of internal energy on volume, i.e. the partial derivative ##\left(\frac{\partial U}{\partial V}\right)_{T,n}## is not exactly zero. This is related to the Joule-Thomson effect.Hi all, I was taught that internal energy of an ideal gas in depending on the temperature which mean during isothermal process, the change in internal energy is equal to zero. Is this statement true?

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BruceW

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