## Work

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

Gabriel Ordonez 2K
Posts: 113
Joined: Sat Jul 20, 2019 12:15 am

### Work

What's the difference in the work equations with their corresponding Delta S equations when one path is reversible and when the other is irreversible?

Eunice Nguyen 4I
Posts: 100
Joined: Sat Aug 17, 2019 12:17 am

### Re: Work

When it's irreversible, the equation for work is w=-Pex*deltaV or -deltan*R*T. When it's reversible, the equation is w=-n*R*T*ln(vf/vi).

Anna Heckler 2C
Posts: 102
Joined: Wed Sep 18, 2019 12:18 am

### Re: Work

When you are finding the work done in a reversible pathway, you must find the sum of a series of infinitesimal steps, which can be accomplished using an integral. The work done by an irreversible pathway involves a rapid change in volume and pressure, so a different formula is used.

Alicia Lin 2F
Posts: 83
Joined: Wed Sep 18, 2019 12:17 am

### Re: Work

delta S equations are the same for both reversible and irreversible. The only difference is that for the irreversible one, S(surr)=0 which makes S(tot)=S(sys) while in the reversible one, S(sys)=-S(surr) which means S(tot)=0

Leslie Almaraz 4G
Posts: 99
Joined: Fri Aug 02, 2019 12:16 am

### Re: Work

Is irreversible always sudden?

Connie Chen 1E
Posts: 51
Joined: Mon Jun 17, 2019 7:24 am

### Re: Work

Leslie Almaraz 4G wrote:Is irreversible always sudden?

Generally, irreversible expansions are quicker than reversible ones because they do not have be changed by an infinitesimally small amount at a time. However, this doesn't always mean that they are very sudden.