化学势判据 S.J.T.U. Phase Transformation and Applications ∑4sdnB≤0 ∑4，d,≤0 这一判据式讨论具体的平衡规律、过程的方向与限度 SJTU Thermodynamics of Materials Spring2006©X.J.Jin Lecture 13 Solution ll
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2006 © X. J. Jin Lecture 13 Solution II 这一判据式讨论具体的平衡规律、过程的方向与限度 ∑ ≤ 0 B μ dnBB 化学势判据 ∑ ≤ 0 i ii μ dn
P,V,Xi影响化学势 S.J.T.U. Phase Transformation and Applications 1,温度的影响 ∂G 298 =-S aT) ,xi 2,压力的影响 气相 aG RT =V L= dG=RTdln P aP P T,xi 3,组成的影响：偏摩尔Gibbs自由能 SJTU Thermodynamics of Materials Spring 2006 ©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 P, V, Xi影响化学势 S T G i xP ⎟ −= ⎠⎞ ⎜⎝⎛ ∂∂ , dT TC S P ∫ = 2980 0298 1，温度的影响 2，压力的影响 V P G i xT ⎟ = ⎠⎞ ⎜⎝⎛ ∂∂ , PRT V = 气相 = ln PRTdGd 3，组成的影响：偏摩尔Gibbs自由能
Thermodynamic activity S.J.T.U. Phase Transformation and Applications Fugacity is defined for gases: dGi=RTd(Infi) Thermodynamic activity of a component,i,is defined as: n0 The fugacity of the componentiin its standard state. The fugacity of a condensed phase is equal to the fugacity of the vapor phase in equilibrium with it. The fugacity of the vapor is equal to the pressure of the vapor,if the vapor in equilibrium with the condensed phase is ideal. 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 )(ln i i = fRTdGd D i i i f f α ≡ Thermodynamic activity Fugacity is defined for gases: Thermodynamic activity of a component, i, is defined as: D i f The fugacity of the component i in its standard state. The fugacity of a condensed phase is equal to the fugacity of the vapor phase in equilibrium with it. The fugacity of the vapor is equal to the pressure of the vapor, if the vapor in equilibrium with the condensed phase is ideal
Relative Partial Molar Quantities S.J.T.U. Phase Transformation and Applications Mixing of A and B to form a solution,the volume changes: AVmixing =VM =Vfimal -Vimitial VM is the volume change upon mixing: 混合前后容量性质变化 Vy =naVA+nBV B-naLa-nBLB Vy=na(VA-La)-nB(V8-LB) 网A-卫 The relative partial molar volume of A The partial molar volume of A in solution relative to the molar volume of pure A. -rel rel Vy =navA +nBVB SJTU Thermodynamics of Materials Spring 2006 ©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 Relative Partial Molar Quantities Δ mixing M == final −VVVV initial AM A B B A A BVnVnVnVnV B −−+= )()( AM A A B B VVnVVnV B −−−= rel B B rel AM A += VnVnV Mixing of A and B to form a solution, the volume changes: VM is the volume change upon mixing: A A −VV The relative partial molar volume of A The partial molar volume of A in solution relative to the molar volume of pure A. rel V A 混合前后容量性质变化
Relative Partial Molar Quantities (2) S.J.T.U. Phase Transformation and Applications M=n4F+nBF公 For one mole of solution, rel rel LM =XAVA +XBVB U,F,G,H,S,V The equations for variations of thermodynamic properties with temperature, pressure,and so on apply to solutions as well as to pure components. dGrl =-SredT G=GA-GA=RTInaA SJTU Thermodynamics of Materials Spring 2006 ©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 Relative Partial Molar Quantities (2) rel B B rel AM A += VnVnV rel B B rel M A A += VxVxV dTSGd rel rel −= A A A rel A =−= RTGGG lnα D For one mole of solution, U, F, G, H, S, V The equations for variations of thermodynamic properties with temperature, pressure, and so on apply to solutions as well as to pure components