Specific study of quasi-chemical equilibriums

We will thoroughly study the equilibrium corresponding to quasi-chemical reactions. From section 3.2.4, we can define the associated properties of these reactions and therefore equilibrium constants. However, frequently, the number of superimposed equilibriums is important in that it leads to very complex calculations. We can simplify these with the help of certain justified approximations. These approximations are of two orders  

We will thus see (section 3.6.3) how thermodynarrrics makes it possible to discuss the effect of a foreign element in an ionic solid quarrtitatively. 

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