Activation Parameters, Thermodynamic Functions and Mechanism

It is interesting that enzyme-catalyzed decarboxylations have a C effect of 1.00, thus invoking a different mechanism. 

So far we have considered rate laws and chemical behavior for one temperature and at normal pressures only. Much information on the mechanism of a reaction may certainly be gleaned from this information alone. However, by carrying out measurements at a number of temperatures or pressures, or in different media, one may obtain useful information, even though the form of the rate law itself rarely changes. 

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