Introduction S.J.T.U. Phase Transformation and Applications GM=RT∑xlnx Ideal solution Slope=-∞ Non-ideal solution:practical solution T1 T2 A xB B Many forms (d) Figure 7.4 Molar properties for an ideal solu- tion A-B:(a)volume of mixing,(b)enthalpy of mixing,(c)entropy of mixing,and (d) Gibbs free energy of mixing. SJTU Thermodynamics of Materials Spring2006©X.J.Jin Lecture 13 Solution Il
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2006 © X. J. Jin Lecture 13 Solution II Introduction Ideal solution Non-ideal solution: practical solution Many forms = ∑ i M ii ln xxRTG
Non-ideal Solution (1) S.J.T.U. Phase Transformation and Applications GM≠RT∑x,lnx A single solution in this region is unstable relative to the mixture of solutions of xBI and XB2. If equilibrium were attained,the single solution would decompose into two solutions because the A xB1 XB2 B Gibbs free energy change XB→ associated with such a Figure 7.6 Plot of G versus xB for a nonideal decomposition is negative. solution,showing positive deviations from Raoult's law.(In the region between xBI and x B2,the system can minimize G by forming mixtures of two solutions,xBi and xB2.) SJTU Thermodynamics of Materials Spring2006©X.J.Jin Lecture 13 Solution Il
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2006 © X. J. Jin Lecture 13 Solution II Non-ideal Solution (1) A single solution in this region is unstable relative to the mixture of solutions of xB1 and xB2. If equilibrium were attained, the single solution would decompose into two solutions because the Gibbs free energy change associated with such a decomposition is negative. ≠ ∑ i M ii ln xxRTG