Le Chatelier-Braun’s principle

Moreover, the systems obey the Le Chatelier-Braun s principle which indicates, that they are stable as regards their chemical composition. We shall discuss this point in the next section. 

Le Chatelier-Braun s Principle or Principle of Mobile Equilibrium This principle was presented already at the end of the nineteenth century and is often mentioned in connection with our current discussion. Chemists use it to predict whether the extent of a reaction in equilibrium will be shifted forward or backward when certain parameters are changed, especially pressure, temperamre, amounts of reactants and products, etc. We have found our answers in what we have already discussed, so we can avoid using this principle. For completeness sake, and because of the problems it causes even today, we will deal with it briefly. We will choose one of the various ways it can be formulated which is close to its original version, but we will avoid misunderstandings by using explanatory additions [in square parentheses] ... 

This formulation of Le Chatelier-Braun s principle discusses how the pair of main quantities (—J , interacts with another such pair, here (—p, V) in the special case of J = const, (or even J = 0, which is unnecessarily special). 

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