(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

In calculus, the work done when a gas expands from volume V_{1}to volume V_{2}is given by

W = ∫^{V2}_{V1}P dV

Use this expression to show that the work done by n moles of gas at temperature T during an isothermal expansion from volume V_{1}to V_{2}is

W = nRT ln(V_{2}/V_{1})

2. Relevant equations

Q = ΔU + W

PV = nRT

3. The attempt at a solution

W = [VP]^{V2}_{V1}= PV_{2}- PV_{1}= PΔV

But I think it should be ΔPΔV since this is an isothermal expansion. W = PΔV is for isobaric since P is constant.

Then I can't even guess where the ln comes from.

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# Homework Help: Calculating the work done during an isothermal expansion using integration

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