Contents of Today S.J.T.U. Phase Transformation and Applications Review previous Solutions Thermodynamic activity Partial molar quantities Relative partial molar quantities Entropy of mixing:ideal solution Enthalpy of mixing:ideal solution Graphical representation SJTU Thermodynamics of Materials Spring 2007 ©X.J.Jin Lecture 11 Solution I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2007 © X. J. Jin Lecture 11 Solution I Contents of Today Review previous Solutions Thermodynamic activity Partial molar quantities Relative partial molar quantities Entropy of mixing: ideal solution Enthalpy of mixing: ideal solution Graphical representation
Nomenclature S.J.T.U. Phase Transformation and Applications Solutions:溶液 Chemical potential:化学位(势) Thermodynamic activity:热力学活度 Ideal solution:理想溶液 Relative partial molar quantities:相对偏摩尔量 Entropy of mixing:混合熵 Graphical representation of partial molar quantities: 偏摩尔量的图示 SJTU Thermodynamics of Materials Spring 2007 ©X.J.Jin Lecture 11 Solution I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2007 © X. J. Jin Lecture 11 Solution I Nomenclature Solutions: 溶液 Chemical potential:化学位(势) Thermodynamic activity:热力学活度 Ideal solution:理想溶液 Relative partial molar quantities:相对偏摩尔量 Entropy of mixing:混合熵 Graphical representation of partial molar quantities: 偏摩尔量的图示
Introduction1:溶液? S.J.T.U. Phase Transformation and Applications Chemical changes among pure components and compounds Solutions:elements or compounds dissolved in one another 何谓溶液? 一 种物质以分子、原子或离子状态分散与另一种物质中所构成的均匀而 又稳定的体系叫溶液。 高等学校教材,无机化学第三版,上册(ISBN7-04-004581-8)328页 布朗运动? Many of the interesting properties of materials and many important chemical reactions take place Thermodynamics of these solutions SJTU Thermodynamics of Materials Spring 2007 ©X.J.Jin Lecture 11 Solution I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2007 © X. J. Jin Lecture 11 Solution I Introduction 1:溶液? Chemical changes among pure components and compounds Solutions: elements or compounds dissolved in one another Many of the interesting properties of materials and many important chemical reactions take place Thermodynamics of these solutions 何谓溶液? 一种物质以分子、原子或离子状态分散与另一种物质中所构成的均匀而 又稳定的体系叫溶液。 高等学校教材,无机化学第三版,上册(ISBN 7-04-004581-8) 328页 布朗运动?
Introduction2:溶液热力学? S.J.T.U. Phase Transformation and Applications 相变是物质由一个相向另一个相的传递过程 扩散是物质由高浓度区向低浓度区的传递过程 化学反应可以看作是物质由反应物向产物的传递过程 在传递过程中化学势将起决定作用。 在恒温恒压下, dG=∑4,dn 再由自由能判据dG≤0可得判据的另一形式(化学势判据): ∑4,dn,≤0 在相变过程中物质总是由化学势高的一相向转向化学势低的 一相,直到两相中的化学势相等为止。而物质在两相中存在的 化学势差△μ:是物质传递的动力。 SJTU Thermodynamics of Materials Spring 2007 ©X.J.Jin Lecture 11 Solution I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2007 © X. J. Jin Lecture 11 Solution I Introduction 2:溶液热力学? 在相变过程中物质i总是由化学势高的一相向转向化学势低的 一相,直到两相中的化学势相等为止。而物质在两相中存在的 化学势差 Δμ i 是物质传递的动力。 = ∑ i ii 在恒温恒压下, dG μ dn 再由自由能判据 dG≤0 可得判据的另一形式(化学势判据): 相变是物质由一个相向另一个相的传递过程 扩散是物质由高浓度区向低浓度区的传递过程 化学反应可以看作是物质由反应物向产物的传递过程 在传递过程中化学势将起决定作用。 ∑ ≤ 0 i ii μ dn
例子 S.J.T.U. Phase Transformation and Applications 在等温等压下,两相平衡是常见的,如复相黄铜(铜一锌合 金)中o黄铜和β黄铜的平衡。设系统0、B两相相接触,在 等温等压下,若组分B(例如铜)有dn.由相进入B相,则o 相中B组分减少dng,而B相中B组分增加dng;其吉布斯函 数变化分别为: o相 B相 dG=ug(-dnB) dG=u(dng) 总的吉布斯函数变化等于 dG=dG+dG(uug)(dng) 组分B有dn.由o相 进入B相 SJTU Thermodynamics of Materials Spring2007©X.寸.Jim Lecture 11 Solution
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2007 © X. J. Jin Lecture 11 Solution I 例子 在等温等压下,两相平衡是常见的,如复相黄铜(铜-锌合 金)中α黄铜和β黄铜的平衡。设系统α 、β两相相接触,在 等温等压下,若组分B(例如铜)有dnB由α相进入β相,则α 相中B组分减少dnB ,而β相中B组分增加dnB ;其吉布斯函 数变化分别为: )( dG −= dnBBαα μ )( dG dnBBββ = μ 总的吉布斯函数变化等于 ))(( dGdGdG dnBBB α αββ −=+= μμ α相 β相 组分B有dnB由α相 进入β相