Entropy of Mixing:Ideal Solution S.J.T.U. Phase Transformation and Applications For an ideal solution, Gl =RTInx a1=X1 The relative partial entropy of component A, S%=-RInxA The molar entropy of mixing for a solution of A+B, SM=xS+x5 SM =-R[xAInxa+xB InxB] SM=-R∑x,lnx For ideal solution with many components, SJTU Thermodynamics of Materials Spring2006©X.J.Jin Lecture 12 Solution IPhase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2006 © X. J. Jin Lecture 12 Solution I Entropy of Mixing: Ideal Solution For ideal solution with many components, i rel i = ln xRTG ( ) B B A xP nP rel A rel A xRT T G T S , , ln ∂− ∂ ⎟ = ⎠⎞ ⎜⎝⎛ ∂∂ −= A rel A −= ln xRS rel B B rel A AM += SxSxS ln[ BBAA ]ln M = − + xxxxRS −= ∑ i M ii ln xxRS For an ideal solution, ii = xa The relative partial entropy of component A, The molar entropy of mixing for a solution of A + B