## Free Expansion

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

Samantha Kan 2L
Posts: 30
Joined: Sat Jul 22, 2017 3:00 am

### Free Expansion

The book mentions the concept of free expansion, and I understand that w=0. What would be an example of free expansion? Would we ever encounter a problem with free expansion in this class?

Curtis Tam 1J
Posts: 105
Joined: Thu Jul 13, 2017 3:00 am

### Re: Free Expansion

Free expansion happens when there is no change in volume or when a reaction, for example, is taking place in a vacuum (no pressure, so P=0).

Esin Gumustekin 2J
Posts: 57
Joined: Thu Jul 27, 2017 3:01 am

### Re: Free Expansion

An example of free expansion is when a gas is allowed to expand into a vacuum. Since there is no opposing force, w=0 and thus the system does no work. The book states that "expansion against zero pressure is called free expansion".

Hope this helps!