2 deltaG equations






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ursulavictorino1K
Posts: 55
Joined: Sun Feb 17, 2019 12:15 am

2 deltaG equations

Postby ursulavictorino1K » Tue Mar 17, 2020 12:30 am

What is the relationship between the equations deltaG=-RTlnK and deltaG= deltaH-TdeltaS?

Jiyoon_Hwang_2I
Posts: 101
Joined: Sat Sep 14, 2019 12:17 am

Re: 2 deltaG equations

Postby Jiyoon_Hwang_2I » Tue Mar 17, 2020 6:10 am

They both solve for the same delta G. You could also set these two equations equal to each other to derive the Van't Hoff Equation

isha dis3d
Posts: 106
Joined: Wed Sep 30, 2020 9:47 pm

Re: 2 deltaG equations

Postby isha dis3d » Mon Feb 01, 2021 6:52 pm

You could use both these equations when solving for the change in the equilibrium constant, Keq, of a chemical reaction given change in temperature, T, given the standard enthalpy change, ΔH⊖, for the process.

Crystal Hsueh 2L
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Re: 2 deltaG equations

Postby Crystal Hsueh 2L » Mon Feb 01, 2021 7:06 pm

Both equations solve for delta G, I believe it is just a matter of what information and values are given to you in the question for you to figure out which of the two equations to use.

Cora Chun 2D
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Re: 2 deltaG equations

Postby Cora Chun 2D » Mon Feb 08, 2021 10:16 am

I believe G=-RTln(K) is for finding equilibrium constants, but the G=H-TS can be used for most other Gibbs free energy problems if you get/solve for enthalpy and entropy. Hope this helps.

Serena Song 1A
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Re: 2 deltaG equations

Postby Serena Song 1A » Mon Feb 08, 2021 11:26 pm

Both will help solve for the same delta G value! It mainly depends on what they give you to work with. Since they solve for the same thing, you can also set them equal to one another

Mursall M 2A
Posts: 60
Joined: Wed Nov 18, 2020 12:20 am

Re: 2 deltaG equations

Postby Mursall M 2A » Tue Feb 09, 2021 9:44 am

It depends on what information you're given to solve for G! If you're given the equilibrium constant, then you should use the first one. But if you're given the delta H and delta S, then you would use the second one. I believe they both should give you the same value!


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