Kinetics, Equilibria, and Electrochemistry

This chapter deals with how chemical reactions proceed their speed or rate, their mechanism, the state(s) accessed between reagents and products, the free energy profile, and theoretical calculations. It also deals with electrochemistry. 

2 ENERGETICS, REACTION COORDINATE, TRANSITION STATES, INTERMEDIATES, AND CATALYSIS 

First of all, the reagent (or reagents) R will occupy some local minimum in the Gibbs free energy G the products (or product) P will be found at 

Schematic change in Gibbs free energy as a function of the reaction coordinate x. R denotes the reagent(s), P represents the product(s) 77 is the transition state (also known as the activated complex), 11 is the reaction intermediate (if it exists). 72 denotes the lower-energy transition state (or activated complex) for the catalyzed reaction. 

the reaction will exhibit a free energy barrier, at the top of which may lay a very short-lived transition state (Tl) or activated complex, with no local minimum in G, and a lifetime of the order of 10-15 s (the time needed for a single vibration), or an intermediate (II) with a small minimum in G and a measurable lifetime 10 12s or longer. Transition state theory was developed in 1935 by Eyring2 and Polanyi.3 

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