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Re^5: Lower Intermediate Energy

sanya
sanya@photonics.ru


>It's actually a theoretical model of an experiment done in gas phase at high temperatures. Sadly, this rules out solvation. About dG, I think you are right since right now I haven't really imposed the actual experimental temperature yet and my results are still at zero Kelvin. It's because of the effect of the systems change in entropy right? So. . . This is so far. . .acceptable. . .right?(please say yes..T_T)

Indeed, taking entropy into account will help if the number of product particles is greater than the number of intermediate particles. For example, one intermediate molecule decomposes into several product molecules (in a catalyzed reaction, it can be CP(catalyst--product adduct) -> C(catalyst) + P(product)). The reversed situation is when, say, two intermediate molecules rearrange to form two product molecules (here, entropy has only slight effect on ΔG) or even combine to form one product molecule (in this case, entropy has the reverse effect). But this can hardly take place in a catalytic reaction (if it does, there should be some additional steps and intermediates missing in the mechanism).


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