《物理化学》习题答案.ppt

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,精选2021版课件,*,物 理 化 学,习题答案,（水,1214,）,1,精选2021版课件,习题,9,计算,lmol,理想气体在下列四个过程中所作的体积功。已知始态体积为,25dm,3,，终态体积为,lOOdm,3,，始态及终态温度均为,100,。,(1),向真空膨胀；,(2),在外压力恒定为气体终态的压力下膨胀；,(3),先在外压力恒定为体积等于,50dm,3,时的气体的平衡压力下膨胀，当膨胀到,50dm,3,(,此时温度仍为,100),以后，再在外压力等于,lOOdm,3,时气体的平衡压力下膨胀；,(4),等温可逆膨胀。,试比较这四个过程的功，比较的结果说明了什么问题,?,解,：（,1,）由于,p(,外）,=0,，,W=0,；,（,2,）由于,p(,外）,=P,2,，,PV=nRT,P,2,=nRT/V,2,W=-P,2,(V,2,-V,1,)=-nRT(V,2,-V,1,)/V,2,=-18.314373.15(100-25)/100=-2327(J),（,3,）,W=W,1,+W,2,=P,2,(V,2,-V,1,)-P,3,(V,3,-V,2,)=-3101(J),（,4,）,W=-nRTlnV,2,/V,1,=-4301(J),以上结果说明，虽然始终态相同，但所作的功不同，其中以等温可逆膨胀所作的功最大。,P17,第一章 热力学第一定律,2,精选2021版课件,习题,23 P25,试求算,2mol 100,、,410,4,pa,的水蒸气变成,100,及,p,的水时，此过程的,U,和,H,。设水蒸气为理想气体，液态水的体积可忽略不计。已知水的摩尔汽化热为,40,67kJmol,-1,。,解：上述过程可分为下面两个过程,100,410,4,pa,H,2,O,(g),100,p,H,2,O,(g),100,p,H,2,O,(l),第一步是理想气体等温过程：,U,1,=H,1,=0,第二步是等温等压下可逆相变：,H,2,=-n,vap,H,m,=-81.34 kJ,U,2,=H,2,p,V =H,2,+2RT =-75.14 kJ,所以全过程的,U,和,H,为：,U=U,1,+U,2,=,-75.14 kJ,H=H,1,+H,2,=-81.34 kJ,3,精选2021版课件,习题,39 P38,已知下列反应在,25,时的热效应为：,（,1,）,Na(s)+1/2Cl,2,(g)=NaCl(s),r,H,m,=,411.0kJmol,1,（,2,）,H,2,(g)+S(s)+2O,2,(g)=H,2,SO,4,(l),r,H,m,=,800.8kJmol,1,（,3,）,2Na(s)+S(s)+2O,2,(g)=Na,2,SO,4,(s),r,H,m,=,1382.8kJmol,1,（,4,）,1/2 H,2,(g)+1/2Cl,2,(g)=HCl(g),r,H,m,=,92.30kJmol,1,计算反应,2 NaCl(s)+H,2,SO,4,(l)=Na,2,SO,4,(s)+2HCl(g),在,25,时的,r,H,m,和,r,U,m,。,解：所求方程,=,（,3,）,+,（,4,）,2,（,1,）,2,（,2,）,r,H,m,=,r,H,m,（,3,）,+2,r,H,m,（,4,）,2,r,H,m,（,1,）,r,H,m,（,2,）,=,55.4,kJmol,1,r,U,m,=,r,H,m,nRT(g)=,r,H,m,2RT,=,50.4,kJmol,1,4,精选2021版课件,习题,41 P38,已知反应,（,1,）,C(,金刚石,)+O,2,(g)=CO,2,(g),r,H,m,（,298K,）,=,395.4kJmol,1,（,2,）,C(,石墨,)+O,2,(g)=CO,2,(g),r,H,m,（,298K,）,=,393.5kJmol,1,求,C(,石墨,)=C(,金刚石,),的,trs,H,m,（,298K,）,解：所求方程,=,（,2,）（,1,）,trs,H,m,=,r,H,m,（,2,）,r,H,m,（,1,）,=,393.5,(,395.4),=,1.9,kJmol,1,5,精选2021版课件,习题,43 P,40,利用标准,mol,生成焓数据，计算下列反应的,r,H,m,(298.15K),。,(1)Cl,2,(g)+2KI(s)=2KCl(s)+I,2,(s),(2)CO(g)+H,2,O(g)=CO,2,(g)+H,2,(g),(3)SO,2,(g)+1/2O,2,(g)+H,2,O(l)=H,2,SO,4,(l),(4)CaCO,3,(s)=CaO(s)+CO,2,(g),(5)CaO(s)+3C(,石墨,)=CaC,2,(s)+CO(g),(6)Fe,2,O,3,(s)+CO(g)=CO,2,(g)+2FeO(s),(7)2H,2,S(s)+SO,2,(g)=3S(s)+2H,2,O(g),(8)Fe,2,O,3,(s)+3C(,石墨,)=4Fe(s)+3CO,2,(g),解：,r,H,m,(298.15K)=,i,f,H,i,(,298.15K),(1)Cl,2,(g)+2KI(s)=2KCl(s)+I,2,(s),f,H,m,(298)kJmol,1,0 -327.65 -435.89 0,r,H,m,(298.15K)=2(-435.89)-2(-327.65,)=-216.5,kJmol,1,6,精选2021版课件,(2)CO(g)+H,2,O(g)=CO,2,(g)+H,2,(g),f,H,m,(298)kJmol,1,110.52 -241.83 -393.51 0,r,H,m,(298.15K),=-41.16,kJmol,1,(3)SO,2,(g)+1/2O,2,(g)+H,2,O(l)=H,2,SO,4,(l),f,H,m,(298)kJmol,1,296.90 0 -285.84 -800.8,r,H,m,(298.15K),=-218.06,kJmol,1,(4)CaCO,3,(s)=CaO(s)+CO,2,(g),f,H,m,(298)kJmol,1,-1206.87 -635.5 -393.51,r,H,m,(298.15K)=,177.86,kJmol,1,(5)CaO(s)+3,C(,石墨,)=CaC,2,(s)+,CO(g),f,H,m,(298)kJmol,1,-635.5 0 -62.76 110.52,r,H,m,(298.15K)=,462.22,kJmol,1,7,精选2021版课件,(6)Fe,2,O,3,(s)+CO(g)=CO,2,(g)+2 FeO(s),f,H,m,(298)kJmol,1,-822.2 110.52 -393.51 -266.5,r,H,m,(298.15K)=,6.2,kJmol,1,(7)2H,2,S(s)+SO,2,(g)=3S(s)+2H,2,O(g),f,H,m,(298)kJmol,1,-20.15 -296.9 0 -241.83,r,H,m,(298.15K),=-146.46,kJmol,1,(8)2Fe,2,O,3,(s)+3,C(,石墨,)=4,Fe(s)+3CO,2,(g),f,H,m,(298)kJmol,1,-822.2 0 0 -393.51,r,H,m,(298.15K)=,463.9,kJmol,1,8,精选2021版课件,习题,45 P42,已知,C,2,H,5,OH,（,l,）在,25,时的燃烧热,为,-1367 kJmol,1,，试用,CO,2,(g),和,H,2,O,（,l,）在,25,时的生,成热，计算,C,2,H,5,OH,（,l,）在,25,时的生成热。,解：查表得,f,H,m,(CO,2,，,g)=-393.514 kJmol,1,，,f,H,m,(H,2,O,，,l)=-285.84 kJmol,1,C,2,H,5,OH,（,l,）,+3O,2,(g)=2 CO,2,(g)+3 H,2,O,（,l,）,c,H,m,(C,2,H,5,OH,，,l)=2,f,H,m,(CO,2,g)+3,f,H,m,(H,2,O,，,l),f,Hm(C,2,H,5,OH,，,l),f,H,m,(C,2,H,5,OH,，,l)=2,f,H,m,(CO,2,g)+3,f,H,m,(H,2,O,，,l),cHm(C,2,H,5,OH,，,l),=,277.6,kJmol,1,9,精选2021版课件,习题,49 P46,试计算在,25,及标准压力下，,1mol,液态水蒸发成水蒸气的气化热。已知,100,及标准压力下液态水的气化热为,2259Jg,-1,，在此温度区间内，水和水蒸气的平均定压摩尔热容分别为,75.3,及,33.2JK,-1,mol,-1,。,解：,evp,H,m,(298K)=,evp,H,m,(373K)+,298,373,C,p,m,(,水,)dT,+,373,298,C,p,m,(,水汽,)dT,=225918+75.375,33.275 Jmol,1,=,43.8,kJmol,1,10,精选2021版课件,P61,解,:,等温等压下不同理想气体混合,:,S=S,A,+S,B,=-n,A,R T ln(V,A,/V)/T+-n,B,RT ln(V,B,/V)/T,=-R(n,A,lnX,A,+n,B,lnX,B,),=2 R ln2 =11.52(J.K-1),因为,Q/T=0,所以,S,0,过程自发进行,第二章 热力学第二定律,11,精选2021版课件,P63,12,精选2021版课件,P77,解：,13,精选2021版课件,14,精选2021版课件,P79,=-5290J,15,精选2021版课件,第三章 化学势,P93,16,精选2021版课件,P93,17,精选2021版课件,P98,18,精选2021版课件,P98,=,19,精选2021版课件,P101,20,精选2021版课件,P104,21,精选2021版课件,第四章 化学平衡,P115,22,精选2021版课件,P119,23,精选2021版课件,P126,24,精选2021版课件,P129,25,精选2021版课件,P134,26,精选2021版课件,P138,27,精选2021版课件,第五章 相平衡,P147,28,精选2021版课件,29,精选2021版课件,P150,30,精选2021版课件,31,精选2021版课件,第七章 电化学,P225,32,精选2021版课件,P234,33,精选2021版课件,P248,34,精选2021版课件,P275,35,精选2021版课件,第八章 表面化学与胶体化学,P291,36,精选2021版课件,P291,37,精选2021版课件,291,38,精选2021版课件,习题,18 P306,39,精选2021版课件,40,精选2021版课件,P306,41,精选2021版课件,P317,21,42,精选2021版课件,P320,24,43,精选2021版课件,P340,第九章 化学动力学基本原理,44,精选2021版课件,P340,45,精选2021版课件,P356,46,精选2021版课件,