Moderators: Chem_Mod, Chem_Admin

Sophia Dinh 1D
Posts: 100
Joined: Thu Jul 25, 2019 12:15 am


Postby Sophia Dinh 1D » Wed Jan 29, 2020 10:25 am

Why do you need to use different equations for irreversible and reversible work?

Posts: 103
Joined: Sat Aug 17, 2019 12:17 am
Been upvoted: 1 time

Re: Work

Postby KeyaV1C » Wed Jan 29, 2020 2:46 pm

Irreversible expansion occurs against a constant external pressure so the equation is just w= - P* Δ V. Reversible expansion has a pressure that keeps changing so then the equation is w= -nRT ln(V2/V1)

Amir Bayat
Posts: 115
Joined: Sat Sep 07, 2019 12:16 am

Re: Work

Postby Amir Bayat » Wed Jan 29, 2020 2:52 pm

irreversible work has a constant pressure so you can simply take it out of the integral

However, reversible work can have a changing pressure, thus the equation changes as both work and the volume change. We must then define pressure in the changing factors it has of nRT, where temperature or the molar concentrations change.

Return to “Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)”

Who is online

Users browsing this forum: No registered users and 2 guests