Free Expansion

$w=-P\Delta V$
and
$w=-\int_{V_{1}}^{V_{2}}PdV=-nRTln\frac{V_{2}}{V_{1}}$

Soumya Ravichandran 4H
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Joined: Fri Sep 28, 2018 12:19 am

Free Expansion

What does free expansion mean? Does it just mean that there was a change in volume, and hence work was present in the system?

Chem_Mod
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Re: Free Expansion

Free expansion refers to a positive change in volume where there is no external pressure that the gas is pushing against (pushing against a vacuum). Thus, work would be zero.

Posts: 59
Joined: Fri Apr 06, 2018 11:04 am

Re: Free Expansion

free expansion is the unrestrained expansion of a gas into a volume

Jake Gordon 1A
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Joined: Fri Sep 28, 2018 12:15 am

Re: Free Expansion

Free expansion irreversible refers to typically isothermal expansion against a vacuum. Delta U, q, and w will all be 0 however a change in entropy will be equal to the entropy change for reversible isothermal expansion using the same values