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Topic: Terminology: Gibbs Free Energy of a Reaction  (Read 1659 times)

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Offline DannyBoy

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Terminology: Gibbs Free Energy of a Reaction
« on: February 19, 2013, 11:39:44 AM »
If someone quotes the Gibbs Free Energy of a Reaction, are they referring to the energy per reaction as it is written or is it per mole of a reactant or product?

Offline Borek

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Re: Terminology: Gibbs Free Energy of a Reaction
« Reply #1 on: February 19, 2013, 12:15:31 PM »
You never know. If they are serious they should explicitly write what they mean.
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Offline ramboacid

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Re: Terminology: Gibbs Free Energy of a Reaction
« Reply #2 on: February 19, 2013, 12:17:06 PM »
Look at the units. Are they kJ or kJ/mol?
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Offline DannyBoy

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Re: Terminology: Gibbs Free Energy of a Reaction
« Reply #3 on: February 19, 2013, 12:31:56 PM »
The problem stems from the CHNOSZ package for R, specifically the subcrt function (http://www.chnosz.net/html/subcrt.html). It will give the value in energy (J or cal) per mol for ΔG° for individual species, but it isn't clear what the units are for reactions. This made me think there was a standard way of doing things.

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