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Topic: work of condensation  (Read 5433 times)

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Offline gloinddark

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work of condensation
« on: May 12, 2010, 11:33:45 AM »
This should be a rather easy question, but I am quite rusty in thermodynamics. so...

I need to find the work done during an isothermal reversible condensation of 1 mol of water at 373K.
I tried tried using w= -nRT ln(Vf/Vi) , but the answer I got is not correct.

n=1, R=8.314, T=373, Vf=0.000018m3, Vi=0.0224m3

Is this the equation I should be using? Are the values correct?

Thanks for your time.

Offline Yggdrasil

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Re: work of condensation
« Reply #1 on: May 12, 2010, 08:11:08 PM »
It's always good to start with the most basic equation for work you know.

Offline gloinddark

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Re: work of condensation
« Reply #2 on: May 26, 2010, 03:13:08 AM »
well that would be work = force x distance ...

(sorry for my late feedback)

Offline Yggdrasil

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Re: work of condensation
« Reply #3 on: May 26, 2010, 06:12:41 PM »
That's good, although a bit too basic.  In thermodynamics, work is usually defined by the equation:

w = - pΔV

(at least for processes that occur at constant pressure).  Try using this as a starting point to answer your question.  What is the change in volume associated with the condensation?

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