Free energy composition curves

Free Energy Phase Diagram

In the free energy formula of Eq 7.36 , nonideality is expressed by the general form gex, the excess free energy. The simplifications used in the prior analyses of ideal melting and phase separation, namely neglecting sex and confining hex to the regular-solution model, are not valid for most binary systems. In order to construct phase diagrams by the common-tangent technique, more elaborate solution models are needed to relate free energy to composition for all likely phases. Figure 8.9 shows...