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