Formula for isothermal, reversible equilibrium

isochoric/isometric:
isothermal:
isobaric:

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KNguyen_1I
Posts: 101
Joined: Sat Aug 17, 2019 12:16 am

Formula for isothermal, reversible equilibrium

Postby KNguyen_1I » Mon Feb 03, 2020 10:19 am

For isothermal reversible reactions, do we always use the equation w=-nRT ln (v1/v2)?
And so I assume for irreversible equation we can use P delta V?

Robin Cadd 1D
Posts: 113
Joined: Thu Jul 11, 2019 12:16 am

Re: Formula for isothermal, reversible equilibrium

Postby Robin Cadd 1D » Mon Feb 03, 2020 10:23 am

Correct! Just remember work = -Pdeltav.

Brian Tangsombatvisit 1C
Posts: 119
Joined: Sat Aug 17, 2019 12:15 am

Re: Formula for isothermal, reversible equilibrium

Postby Brian Tangsombatvisit 1C » Mon Feb 03, 2020 10:25 am

When using the equation -nRTln(V2/V1) for reversible reactions, does n stand for the change in moles after the reaction takes place or does it stand for the total number of moles?

sarahforman_Dis2I
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Joined: Sat Aug 17, 2019 12:18 am

Re: Formula for isothermal, reversible equilibrium

Postby sarahforman_Dis2I » Mon Feb 03, 2020 12:32 pm

Brian Tangsombatvisit 1C wrote:When using the equation -nRTln(V2/V1) for reversible reactions, does n stand for the change in moles after the reaction takes place or does it stand for the total number of moles?


I believe n stands for the net amount of moles produced in the reaction (so final amount of moles-initial moles).

Verity Lai 2K
Posts: 100
Joined: Sat Aug 24, 2019 12:18 am

Re: Formula for isothermal, reversible equilibrium

Postby Verity Lai 2K » Tue Feb 04, 2020 10:03 pm

Yeah, for reversible expansion, the equation for work is w=-nRTln(v2/v1) and for irreversible expansion, the equation is w=-PexdeltaV. They are both essentially the same, except the irreversible expansion has constant pressure, while reversible expansion has change in pressure.


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