Hello all,
Does anyone know if there is a theoretical maximum and minimum for the Gibbs free energy? In other words, under constant physiological conditions, can one calculate the possible theoretical thermodynamics range that any reaction falls under?
Thank you
we recommended this paper
Article A Gibbs Free Energy-Based Assessment of Microbial Electrocatalysis
Since I'm not familiar enough with the biochemistry (and especially its math), I used data from equilibrator (http://equilibrator.weizmann.ac.il) to calculate the range and distribution of all chemical species contained within their database of component contribution calculated formation energy (n=12518). At pH of 7.0, ionic strength of 0.1 M and temperature of 298.15 Kelvin the results are a min of -7570.203252292651 and a max of 8901.193973225647 (attached is a histogram of the results).
This is not ideal since I would like to know the theoretical thermodynamic ranges for all possible reactions, and here we have the formation energy of chemical species.
The third law of thermodynamics is the answer.
As the entropy will not change at absolute zero, the Gibbs free energy would only depend on the entlapy.
Actually, for chemical process calculations, the chemist are interseted on the thermodynamic changes. So, the Gibbs free energy change will reach a minimum value when the change of entropy equals to zero.
On the other hand, there is no a consensus about the maximum value that can reach the free gibbs energy. It would depend only on the intrinsc characteristics of the evaluated process
Regards
Daniel
Thanks a lot Daniel Olivo
Actually, for chemical process calculations, the chemist are interseted on the thermodynamic changes. So, the Gibbs free energy change will reach a minimum value when the change of entropy equals to zero.
That's great news. So it means that the minima is: -TS where T is temperature in Kelvin and S is the entropy of the system.
On the other hand, there is no a consensus about the maximum value that can reach the free gibbs energy. It would depend only on the intrinsc characteristics of the evaluated process
So does it mean that I can extract from a database the Gibbs free energy of species and combine them to emulate theoretical reaction Gibbs free energy change of these reactions?
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