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I'm currently taking a Biophysics lecture. There's a vast usage of the terms Enthalpy and Gibbs Free Energy. I understood that most of the time, we're dealing with the Gibbs Free Energy, because our experiment is at constant Temperature (e.g. room temperature) and constant Pressure (e.g. 1 atm). So the second law of Thermodynamics tells me, that Entropy cannot decrease and therefore the Gibbs Free Energy is at minimum in Equilibrium (with some intermediate steps).
So now I've read a paper about tunneling and they make use of the Enthalpy here: http://www.sciencemag.org/content/192/4243/1002.refs
I give you an abstract on the contents: they have hemoglobin and bind CO onto it. They flash it with light and the CO dissociates. Now the CO rebinds onto hemoglobin after some time. The rebinding process can be modeled as some kind of chemical reaction. This includes a activation Energy. As we have multiple protein conformations, each has its own activation Energy. So we have a whole spectrum of proteins with its activation Energys in the range of 1 to 6 kJ/mole.
They used the "Enthalpy" in the paper above. I'm wondering now, why they didn't choose the Gibbs Free Energy (because for the reasons above).
I have a thought on that, but I'm not sure, perhaps someone could confirm and make it a little more obvious to me: In the above experiment, we take a closer look on rebinding on different Temperatures. So this might be somehow related to the fact, that we cannot use the Gibbs Free Energy…
So now I've read a paper about tunneling and they make use of the Enthalpy here: http://www.sciencemag.org/content/192/4243/1002.refs
I give you an abstract on the contents: they have hemoglobin and bind CO onto it. They flash it with light and the CO dissociates. Now the CO rebinds onto hemoglobin after some time. The rebinding process can be modeled as some kind of chemical reaction. This includes a activation Energy. As we have multiple protein conformations, each has its own activation Energy. So we have a whole spectrum of proteins with its activation Energys in the range of 1 to 6 kJ/mole.
They used the "Enthalpy" in the paper above. I'm wondering now, why they didn't choose the Gibbs Free Energy (because for the reasons above).
I have a thought on that, but I'm not sure, perhaps someone could confirm and make it a little more obvious to me: In the above experiment, we take a closer look on rebinding on different Temperatures. So this might be somehow related to the fact, that we cannot use the Gibbs Free Energy…
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