Units for delta G

$\Delta G^{\circ} = -nFE_{cell}^{\circ}$

Riya Sood 4G
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Units for delta G

When calculating dela G= -(n)(F)(Ecell), will the units for delta G be KJ/mol or just KJ?

Asha Agarwal 1E
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Re: Units for delta G

The units will just be in kJ since the units in n and F cancel in terms of moles.

VPatankar_2L
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Re: Units for delta G

Since one Faraday is 96485 C/mol, it can be multiplied by n (moles) in the equation delta G = -nFE to just get kJ.

Alice Chang 2H
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Re: Units for delta G

Asha Agarwal 1E wrote:The units will just be in kJ since the units in n and F cancel in terms of moles.

I thought ∆G was in units of kJ since the textbook omits the assumed "/mol" part. A TA mentioned this to me as well in a previous topic. Was I wrong this whole time?

RobertXu_2J
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Re: Units for delta G

Gibbs free ENERGY. delta G is literally referring to a change in energy, so it has the same units as those for energy, which is joules, so the answer would be kJ (kilojoules). Additionally, if you use the equation, you will find that it is kJ

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Re: Units for delta G

VPatankar_2L wrote:Since one Faraday is 96485 C/mol, it can be multiplied by n (moles) in the equation delta G = -nFE to just get kJ.

What are the units for E and how do we get to Joules from coulombs?

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Re: Units for delta G

delta G is given in kJ

Rodrigo2J
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Re: Units for delta G

the unites for delta G would be kilojoules.

VPatankar_2L
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Re: Units for delta G

VPatankar_2L wrote:Since one Faraday is 96485 C/mol, it can be multiplied by n (moles) in the equation delta G = -nFE to just get kJ.

What are the units for E and how do we get to Joules from coulombs?

The units for E are Volts, and one Volt = 1 J/C. So, when you multiply n (moles) by F (C/mol) and E ( V = J/C) you get J.

Jasmine W 1K
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Re: Units for delta G

The unit would be kJ.

Elizabeth Harty 1A
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Re: Units for delta G

What is the difference between delta g naught and delta g?

Riya Sood 4G
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Re: Units for delta G

Elizabeth Harty 1A wrote:What is the difference between delta g naught and delta g?

Delta G naught is for standard conditions at 25 degree celsius, 1 atm, 1 M. Delta G is for non-standard conditions.

Caroline Beecher 2H
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Re: Units for delta G

Elizabeth Harty 1A wrote:What is the difference between delta g naught and delta g?

The units when you are talking about delta G naught would be kilojoules per mole, whereas under nonstandard conditions the units for delta G would be just kilojoules.

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Re: Units for delta G

Alan Cornejo 1a
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Re: Units for delta G

Your units in the end, end up canceling eachother out with the exception of kj which is what you are calculating for deltaG.

Nicoli Peiris 1B
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Re: Units for delta G

The units would kJ since the other units cancel.

Alison Perkins 2B
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Re: Units for delta G

the moles will cancel between n (mol) and F (C/mol) so it will be in kJ

Halle Villalobos 3E
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Re: Units for delta G

Hi! Delta G is given in kJ.

SLai_1I
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Re: Units for delta G

The unit for delta G is just kJ.

SahajDole_1C
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Re: Units for delta G

The units would be in kJ

Lesly Lopez 3A
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Re: Units for delta G

The unites for delta G would be kilojoules. Follow up question: this is what units for an answer right? Like if it was in J that it is for sure that you need to convert to kj right?

Sukhkiran Kaur 3I
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Re: Units for delta G

It would just be in kJ i believe.

jia207
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Re: Units for delta G

Delta G units would be in kj!

DMaya_2G
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Re: Units for delta G

The units for delta G are just in kj.

emwoodc
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Re: Units for delta G

The units for delta G are almost always kj

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Re: Units for delta G

They would just be in kJ once all the units cancel out.

Ava Nickman
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Re: Units for delta G

units are kJ

Inderpal Singh 2L
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Re: Units for delta G

I think delta G is always in kJ.

Brandon Le 3C
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Re: Units for delta G

In the equation delta G = -nFEcell, the n = mol e-, F = 96485 J/V.mol e-, and Ecell = V. When these variables are multiplied, the mol e- and V cancel out, leaving just the J. However, the question may ask you to convert from J to kJ, in which 1000 J = 1 kJ.

Aria Movassaghi 1A
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Re: Units for delta G

once things cancel out, we are just left with kj for units

aashmi_agrawal_3d
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Re: Units for delta G

The units would be kJ.

nayha a 1E
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Re: Units for delta G

The units for delta G should be in kJ.