Question 8 S.J.T.U. Phase Transformation and Applications 298K时，已知甲醇蒸气的标准摩尔Gibbs生成自由能( CH3OH,g)为一161.92Jmol-1,试求甲醇液体的标准摩尔 Gibbs2生成自由能(CH3OH,I)。己知该温度下甲醇液体的 饱和蒸气压为16.343kPa。假定气体为理想气体。 △G=△G°+RTInJ 4G=0 16.343kPa AG=-RT In J (equlbrum)=-RT'In Ke Gas △G=0 △G°=dG)+eGE-bGg-cG& Liquid Ka b 01 aBQC SJTU Thermodynamics of Materials Spring 2008 ©X.J.Jin Lecture 9 electrochemistry I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2008 © X. J. Jin Lecture 9 electrochemistry I Question 8 c C b B e E d D K αα αα α = o o o o o D E B C −−+=Δ cGbGeGdGG 298K时，已知甲醇蒸气的标准摩尔Gibbs生成自由能（ CH3OH，g）为－161.92kJ·mol-1，试求甲醇液体的标准摩尔 Gibbs生成自由能（CH3OH，l）。已知该温度下甲醇液体的 饱和蒸气压为16.343kPa。假定气体为理想气体。 α +Δ=Δ ln JRTGG o α KRT α JRTG mequilibriu −=Δ ln ( ) −= ln o ΔG 0 = o i i i f f α ≡ Liquid ΔG=0 16.343kPa Gas
5.6 ELLINGHAM DIAGRAMS (4) S.J.T.U. Phase Transformation and Applications 101-3106 1010-1:04104 1. 直线位置越低，元素与氧 化合的能力越大，相应的 氧化物越稳定； 2. 位置在下的金属或元素可 以把较上面的金属从氧化 物中还原出来； 3.炼铁过程，铁以下进入炉 渣，铁以上进入铁液，决 定何时加入配料。 材一子，0 局限 2+92…20 平衡的热力学讨论 200 10-10o 1000 110-0 10- 凝聚相都是纯物质 Figure 5.7 Ellingham diagram for some oxides SJ I U Ihermodynamics ot Materials Spring 2UU8 ©X.J.Jin Lecture 9 electrochemistry I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2008 © X. J. Jin Lecture 9 electrochemistry I 5.6 ELLINGHAM DIAGRAMS (4) 1. 直线位置越低，元素与氧 化合的能力越大，相应的 氧化物越稳定； 2. 位置在下的金属或元素可 以把较上面的金属从氧化 物中 还原出来； 3. 炼铁过程，铁以下进入炉 渣，铁以上进入铁液，决 定何时加入配料。 局限 平衡的热力学讨论 凝聚相都是纯物质
5,7 VARIATION OF EQUILIBRIUM CONSTANT WITH TEMPERATURE S.J.T.U. Phase Transformation and Applications d(△G)=-△SdT △G°=△H°-T△S dAG)=Car- H°dr T T Multiplying by 1/T,we obtain: T aag）)=a-RInK。）)=AHrd宁） SJTU Thermodynamics of Materials Spring2008©X.J.Jin Lecture 9 electrochemistry I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2008 © X. J. Jin Lecture 9 electrochemistry I 5.7 VARIATION OF EQUILIBRIUM CONSTANT WITH TEMPERATURE Multiplying by 1/T , we obtain: dTSGd o o )( Δ−=Δ o o o Δ−Δ=Δ STHG dT T H dT T G Gd o o o Δ − Δ )( =Δ dT T H dT T G T Gd 2 2 )( o o o Δ −= Δ − Δ ) 1()ln()( T dHKRd TG d o o Δ=−= Δ α ) 1 )(ln (T d RH Kd o Δ α −= G 1 d( ) H d( ) T T Δ = Δ o o
5.8 GASES DISSOLVED IN METALS (SIEVERT'S LAW) S.J.T.U. Phase Transformation and Applications H2(g)=2H (in copper solution) 0H,(g) an [H] 1.0 ap 1 cm3(STP)/100 gCu [H](concentration of H)-> Figure 5.10 Plot of activity of dissolved hydrogen versus [I]=K&2P2 concentration. SJTU Thermodynamics of Materials Spring 2008 ©X.J.Jin Lecture 9 electrochemistry I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2008 © X. J. Jin Lecture 9 electrochemistry I 5.8 GASES DISSOLVED IN METALS (SIEVERT’S LAW) 2)( HgH (in copper solution) 2 = )( 2 2 gH H K α α α = α H = [ ] H [ ] 2 2 PH H Kα = [ ] 2/12/1 H2 = α PKH
5.9 CHEMICAL EQUILIBRIUM AND ADLABATIC S.J.T.U. FLAME TEMPERATURES Phase Transformation and Applications Not completion First law Chemical equilibrium Chemical equilibrium Egs 5.36a and 5.36b First law (Chemical equilibrium) 0.8 Eq.5.37(AFT) 0.6 人 0.4 0.2 0 2,000 4,000 6,000r·8,000 10,000-12,00014.000 Tempperature(→ Figure 5.11 The extent of the reaction 2H-H,as a function of temperature for the AFT and chemical equilibrium calculations (Egs.5.37 and 5.36a, respectively). SJTU Thermodynamics of Materials Spring2o08©X.J.Jin Lecture 9 electrochemistry I
Phase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Spring 2008 © X. J. Jin Lecture 9 electrochemistry I 5.9 CHEMICAL EQUILIBRIUM AND ADLABATIC FLAME TEMPERATURES (1) Not completion First law Chemical equilibrium First law Chemical equilibrium