Minimum reaction concept definition

The concept of free energy is useful in defining the possibility of a reaction and in determining its limiting or equilibrium conversion. The formal definition of the equilibrium state of a chemical reaction is the state for which the total free energy is a minimum. Thus the well-known rule reaction can occur if AG is negative it cannot occur if AG is positive. Now we shall present the main features of the equilibrium state for ideal and nonideal gases. 

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