Equilibrium for a Single Reaction

So far, we have examined specific cases to illustrate the effect of kinetics vs. thermodynamics upon reacting systems (butadiene) and how the thermodynamic property Gibbs energy allows us to calculate equilibrium compositions by quantifying the trade-off between energy and entropy (HCl). We now wish to develop a general approach so that we can analyze the chemical reaction equilibria for any system of interest. 

The reaction we considered in Reaction (9.1), formation of HCl from Hg and Cfy, can be written as follows  

To generalize, we can introduce v , the stoichiometric coefficient. The stoichiometric coefficient tells us the proportion in which a given species is produced, or reacts, given a particular reaction. By convention, the stoichiometric coefficient is positive for products, negative for reactants, and zero for inerts, that is. 

We now wish to generalize this approach to any possible reaction. This is particularly useful for making complex chemical equilibrium analysis amenable to computer 

By defining the species, Aj, along with their stoichiometric coefficients, v, in Reaction (9.5), a given chemical reaction is completely specified. Moreover, the production or consumption of reacting species is not independent rather. Reaction (9.5) constrains how each of the reacting species changes. 

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Equilibrium for a single reaction in the liquid-phase. A significant proportion of fine chemistry processes occur in the liquid phase. The equilibrium constant is expressed by Eqn. (5.4-8), which can be rewritten as ... 

Consequently, the criterion for chemical equilibrium for a single reaction is... 

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