Hi! In lecture, Dr. Lavelle used the deltaGnaught = (the sum of the deltaG products) - (the sum of the deltaG reactants) equation to solve for deltaG naught of the reaction. However, I noticed that the reaction takes place at T = 1943 K, and I recalled from some previous homework problems that we weren't able to use this equation at temperatures other than 298 K. Instead, we had to calculate delta H naught and delta S naught and then use the deltaG naught = (deltaH naught) - T*(deltaS naught) equation to solve for deltaG naught.
Are we able to use deltaGnaught = (the sum of the deltaG products) - (the sum of the deltaG reactants) at temperatures other than 298 K? Thanks in advance!
Lecture Example/delta G naught at a different temp
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Re: Lecture Example/delta G naught at a different temp
Yes. This is because the equation for
delta G0 = RTlnK
accounts for temperatures that are not 298 K. Hence, delta G0 can be found at different temperatures. As for delta G0 = products - reactants, the Gibbs free energy values for the products and reactants must be corresponding to the same temperature as the reaction.
delta G0 = RTlnK
accounts for temperatures that are not 298 K. Hence, delta G0 can be found at different temperatures. As for delta G0 = products - reactants, the Gibbs free energy values for the products and reactants must be corresponding to the same temperature as the reaction.
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Re: Lecture Example/delta G naught at a different temp
Akash J 1J wrote:Yes. This is because the equation for
delta G0 = RTlnK
accounts for temperatures that are not 298 K. Hence, delta G0 can be found at different temperatures. As for delta G0 = products - reactants, the Gibbs free energy values for the products and reactants must be corresponding to the same temperature as the reaction.
That makes sense, thank you so much!
Re: Lecture Example/delta G naught at a different temp
but if delta G0 can be culauated at different temperatures why is it defined as the standard change in gibbs free energy if it doesn't have to be at 298K?
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