Units for delta G


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Riya Sood 4G
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Units for delta G

Postby Riya Sood 4G » Sat Feb 29, 2020 10:52 pm

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

Postby Asha Agarwal 1E » Sat Feb 29, 2020 10:54 pm

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

Postby VPatankar_2L » Sat Feb 29, 2020 11:16 pm

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

Postby Alice Chang 2H » Sun Mar 01, 2020 12:48 am

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

Postby RobertXu_2J » Sun Mar 01, 2020 3:07 am

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

Kayla Maldonado 1C
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Re: Units for delta G

Postby Kayla Maldonado 1C » Sun Mar 01, 2020 4:00 am

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?

BAlvarado_1L
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Re: Units for delta G

Postby BAlvarado_1L » Sun Mar 01, 2020 8:48 am

delta G is given in kJ

Rodrigo2J
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Re: Units for delta G

Postby Rodrigo2J » Sun Mar 01, 2020 11:30 am

the unites for delta G would be kilojoules.

VPatankar_2L
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Re: Units for delta G

Postby VPatankar_2L » Sun Mar 01, 2020 12:48 pm

Kayla Maldonado 1A wrote:
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

Postby Jasmine W 1K » Sun Mar 01, 2020 4:59 pm

The unit would be kJ.

Elizabeth Harty 1A
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Re: Units for delta G

Postby Elizabeth Harty 1A » Sun Mar 01, 2020 5:01 pm

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

Riya Sood 4G
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Re: Units for delta G

Postby Riya Sood 4G » Tue Mar 03, 2020 3:42 pm

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

Postby Caroline Beecher 2H » Wed Mar 04, 2020 2:30 pm

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.

BAlvarado_1L
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Re: Units for delta G

Postby BAlvarado_1L » Tue Mar 17, 2020 10:18 am

Your answer will be given in KJ

Alan Cornejo 1a
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Re: Units for delta G

Postby Alan Cornejo 1a » Tue Mar 17, 2020 5:08 pm

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

Postby Nicoli Peiris 1B » Mon Feb 22, 2021 12:29 pm

The units would kJ since the other units cancel.

Alison Perkins 2B
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Re: Units for delta G

Postby Alison Perkins 2B » Mon Feb 22, 2021 12:45 pm

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

Postby Halle Villalobos 3E » Mon Feb 22, 2021 2:57 pm

Hi! Delta G is given in kJ.

SLai_1I
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Re: Units for delta G

Postby SLai_1I » Mon Feb 22, 2021 2:57 pm

The unit for delta G is just kJ.

SahajDole_1C
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Re: Units for delta G

Postby SahajDole_1C » Mon Feb 22, 2021 3:03 pm

The units would be in kJ

Lesly Lopez 3A
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Re: Units for delta G

Postby Lesly Lopez 3A » Mon Feb 22, 2021 3:28 pm

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

Postby Sukhkiran Kaur 3I » Mon Feb 22, 2021 4:11 pm

It would just be in kJ i believe.

jia207
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Re: Units for delta G

Postby jia207 » Mon Feb 22, 2021 4:48 pm

Delta G units would be in kj!

DMaya_2G
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Re: Units for delta G

Postby DMaya_2G » Mon Feb 22, 2021 5:35 pm

The units for delta G are just in kj.

emwoodc
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Re: Units for delta G

Postby emwoodc » Thu Feb 25, 2021 7:12 pm

The units for delta G are almost always kj

LarisaAssadourian2K
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Re: Units for delta G

Postby LarisaAssadourian2K » Thu Feb 25, 2021 7:33 pm

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

Ava Nickman
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Re: Units for delta G

Postby Ava Nickman » Thu Feb 25, 2021 8:23 pm

units are kJ

Inderpal Singh 2L
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Re: Units for delta G

Postby Inderpal Singh 2L » Thu Feb 25, 2021 9:20 pm

I think delta G is always in kJ.

Brandon Le 3C
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Re: Units for delta G

Postby Brandon Le 3C » Thu Feb 25, 2021 10:35 pm

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

Postby Aria Movassaghi 1A » Thu Feb 25, 2021 11:08 pm

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

aashmi_agrawal_3d
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Re: Units for delta G

Postby aashmi_agrawal_3d » Thu Feb 25, 2021 11:27 pm

The units would be kJ.

nayha a 1E
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Re: Units for delta G

Postby nayha a 1E » Thu Feb 25, 2021 11:33 pm

The units for delta G should be in kJ.


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