# Chapter 12: Equilibrium Conditions in Multicomponent Systems

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This chapter applies equilibrium theory to a variety of chemical systems of more than one component.  Two different approaches will be used as appropriate: one based on the relation $$\mu_i\aph=\mu_i\bph$$ for transfer equilibrium, the other based on $$\sum_i\!\nu_i\mu_i=0$$ or $$K=\prod_i a_i^{\nu_i}$$ for reaction equilibrium.