Reversible vs Irreversible

isochoric/isometric: $\Delta V = 0$
isothermal: $\Delta T = 0$
isobaric: $\Delta P = 0$

Rita Chen 1B
Posts: 112
Joined: Sat Jul 20, 2019 12:15 am

Reversible vs Irreversible

Is the only time we need to differentiate between reversible and irreversible when calculating work with: eversible: - nRT ln (v1/v2) and -Pext ΔV and when calculating delta S?

ALegala_2I
Posts: 102
Joined: Thu Jul 11, 2019 12:17 am

Re: Reversible vs Irreversible

From what we learned, we only distinguished our calculation for reversible and irreversible to calculate work and the total change in entropy of the universe.

Kevin Xu 4F
Posts: 50
Joined: Fri Aug 09, 2019 12:16 am

Re: Reversible vs Irreversible

Yes, those equations can be used to find the change in entropy but also keep in mind what reversible and irreversible reactions mean. A reversible reaction is one that has infinitesimal changes that can be reversible by addition or subtraction at any given point in time, whereas irreversible changes immediately and cannot be reverted to its original state. Reversible reactions are most commonly used in the context of isothermal reactions where delta U and delta H equal 0.

CameronDis2K
Posts: 51
Joined: Wed Feb 20, 2019 12:18 am

Re: Reversible vs Irreversible

Correct, reversible is applied to the equation W = -pexdeltaV, when the change in p is constant. The other equation is used when the process is irreversible, and usually isothermal (deltaT = 0).

Alison Trinh 1E
Posts: 104
Joined: Thu Jul 25, 2019 12:16 am

Re: Reversible vs Irreversible

How can you tell a process is reversible or irreversible without having a visual/picture?

Rafsan Rana 1A
Posts: 55
Joined: Sat Aug 24, 2019 12:16 am

Re: Reversible vs Irreversible

Irreversible processes are usually spontaneous and quick where as irreversible processes are slow and maintain equilibrium throughout the entirety of the process. However, I believe it will be clearly stated or inferred in any test.