Using Gibbs free energy –composition to conclude phase diagrams of regular solution:
Consider the binary system A-B at a temperature T wich is below Tm(B) ,the melting temperature of B and above Tm(A) , and the system forms
Raoulation ideal liquid and solid solution. At any composition the formation of a homogeneous liquid solution from pure liquid A and pure solid B can be considered as the mixing of XB moles of liquid B and XA moles of liquid A to form an ideal liquid solution from liquid A and solid B is given by:
By using quick basic program to graph phase diagrams at different temperatures when
A-B forms regular liquid and solid solution . The Gibbs free energy of mixing curve at 1000 K as shown in Fig.1-a ,at thus the free energy of mixing are At temperature lower than & the standard state for both components and the Gibbs free energy as:
Fig.(2): the Gibbs free energy curves at various temperatures and the phase diagram for a binary system which forms regular solid solution in which =10000 J and regular liquid solution in which =-2000J
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