## Irreversible process

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

Blake_Katsev_2E
Posts: 113
Joined: Wed Sep 21, 2016 2:57 pm

### Irreversible process

Why is there no work done in free expansion? and does free expansion mean irreversible?

vsyacoubian2A
Posts: 63
Joined: Fri Jul 22, 2016 3:00 am

### Re: Irreversible process

When something diffuses from high concentration to low concentration, it is not doing work. For example, if it were to push on a piston during diffusion and move it, it would be doing work. Diffusion is an irreversible process. You can go from high to low concentrations but not low to high without the help of some force.

Janice Kim 3I
Posts: 33
Joined: Wed Sep 21, 2016 2:56 pm

### Re: Irreversible process

Free expansion is saying that the particles, let's say from a reaction, is diffusing outwards freely. There is no work involved because these particles do not need to exert any energy (do work) to freely expand.