1.NO是汽车尾气的主要污染源,有人设想以加热分解的方法来消除之2NON2+O2试从热力学角度判断该方法能否实现?解:518022590..HmrkJ·mol-162242762101420561191....SmrJ·mol-1·K-1该反应要实现必须mrG<0所以高温不利2.设汽车内燃机内温度因燃料燃烧反应达到1573K,试计算此温度时下列反应1/2N2(g)+1/2O2(g)NO(g)的rmG和K解:molkJSHGmBmfBmr/77.7010)138.2052161.19121761.210(157325.9015733331046.4ln157310314.877.70lnKKKRTGmr3.蔗糖(C12H22O11)在人体内的代谢反应为:C12H22O11(s)+12O2(g)12CO2(g)+11H2O(l)假设其反应热有30%可转化为有用功,试计算体重为70kg的人登上3000m高的山(按有效功计算),若其能量完全由蔗糖转换,需消耗多少蔗糖?解:A=70kg3000m=2.1105kgm=2.11059.8J=2.1103kJrH=2.1103kJ/30%=7.0103kJrHm=11(285.830kJmol1)+12(393.509kJmol1)(2222kJmol1)=5644kJmol1=rH/rHm=7.0103kJ/5644kJmol1=1.24molm(C12H22O11)=1.24342.3=425g4.利用附录III的数据,计算298.15K时下列反应的rmH(1)Ca(OH)2(s)+CO2(g)CaCO3(s)+H2O(l)(2)CuO(s)+CO(g)Cu(s)+CO2(g)(3)2SO2(g)+O2(g)2SO3(g)(4)CH3COOH(l)+2O2(g)2CO2(g)+2H2O(l)解:mfBmrHH(1)mrH=(–1206.92)+(–285.83)–(–986.09)–(–393.51)=–113.15kJmol1(2)mrH=0+(–393.51)-(–157.3)–(–110.53)=-125.68kJmol1(3)mrH=2[(–395.72)–(–296.83)]=–197.78kJmol1(4)mrH=2(–393.51)+2(–285.83)–(–484.5)=–874.18kJmol15.已知下列化学反应的反应热:(1)C2H2(g)+5/2O2(g)2CO2(g)+H2O(g);rHm=1246.2kJmol1(2)C(s)+2H2O(g)CO2(g)+2H2(g);rHm=+90.9kJmol1(3)2H2O(g)2H2(g)+O2(g);rHm=+483.6kJmol1求乙炔(C2H2,g)的生成热fHm。解:反应2(2)(1)2.5(3)为:2C(s)+H2(g)C2H2(g)fHm=2rHm(2)rHm(1)2.5rHm(3)=[290.9(1246.2)2.5483.6]kJmol1=219.0kJmol16.高炉炼铁中的主要反应有:C(s)+O2(g)CO2(g)1/2CO2(g)+1/2C(s)CO(g)CO(g)+1/3Fe2O3(s)2/3Fe(s)+CO2(g)(1)分别计算298.15K时各反应的rmH和各反应rmH值之和;(2)将上列三个反应式合并成一个总反应方程式,应用各物质298.15K时的fmH数据计算总反应的反应热,与⑴计算结果比较,并作出结论。解:(1)mfBmrHH51.3930051.393)1(mrHkJmol123.860)51.393(2153.110)2(mrHkJmol125.8)2.824(31)53.110()51.393(0)3(mrHkJmol1mrH)4()2()1(mrmrmrHHH=53.315kJmol1(2)53.31500)2.824(31)51.393(230mfBmrHHkJmol1无论是一步反应或多步反应化学反应热效应总和总是相等的。7.利用附录III,判断下列反应298.15K能否自发向右进行。(1)2Cu+(aq)Cu2+(aq)+Cu(s)(2)AgCl(s)+Br(aq)AgBr(s)+Cl(aq)(3)4NH3(g)+5O2(g)4NO(g)+6H2O(g)(4)4NO(g)+6H2O(g)4NH3(g)+5O2(g)解:mfBmrGG(1)mrG=65.49+049.982=34.47kJmol1<0能自发反应(2)mrG=(96.9)+(131.22)(109.79)(103.96)=14.38kJmol1<0能自发反应(3)mrG=4(86.55)+6(228.58)4(16.45)0=959.48kJmol1<0(4)mrG=4(16.45)+04(86.55)6(228.58)=959.48kJmol1>08.由软锰矿二氧化锰制备金属锰可采取下列两种方法:(1)MnO2(s)+2H2(g)Mn(s)+2H2O(g);(2)MnO2(s)+2C(s)Mn(s)+2CO(g);上述两个反应在25℃,100kPa下是否能自发进行?如果考虑工作温度愈低愈好的话,则制备锰采用哪一种方法比较好?解:(1)98.8)58.228(2)14.466()298(KGmrkJmol1>0(2)819117137214466298.).().()K(GmrkJmol1>0所以两个反应在25℃,100kPa下都不能自发进行。一式的mrH=36.39kJmol1mrS=95.24kJmol1T1=382K一式的mrH=298.98kJmol1mrS=362.28kJmol1T2=825K仅考虑温度时,选(1)有利9.定性判断下列反应的rmS是大于零还是小于零:(1)Zn(s)+2HCl(aq)ZnCl2(aq)+H2(g)(2)CaCO3(s)CaO(s)+CO2(g)(3)NH3(g)+HCl(g)NH4Cl(s)(4)CuO(s)+H2(g)Cu(s)+H2O(l)解:(1)mrS>0(2)mrS>0(3)mrS<0(4)mrS<010.糖在人体中的新陈代谢过程如下:C12H22O11(s)+12O2(g)12CO2(g)+11H2O(l)若反应的吉布斯函数变rGm只有30%能转化为有用功,则一匙糖(3.8g)在体温37℃时进行新陈代谢,可得多少有用功?(已知C12H22O11的fHm=2222kJmol1Sm=360.2Jmol1K1)解:C12H22O11(s)+12O2(g)12CO2(g)+11H2O(l)fHm/kJmol122220393.509285.830Sm/Jmol1K1360.2205.138213.7469.91rHm=[11(285.830)+12(393.509)(2222)]kJmol1=5645kJmol1rSm=[1169.91+12213.7412205.138360.2]Jmol1K1=512.03Jmol1K1rGm=rHmTrSm=5645kJmol1310.15K512.03103kJmol1K1=5803kJmol1=nB/B=3.8g/342gmol1=1.11102molW有用功=30%rG=30%rGm=30%(5803kJmol1)1.11102mol=19kJ负号表示系统对环境做功。11.已知反应2H2(g)+2NO(g)2H2O(g)+N2(g)的速率方程v=kc(H2)c2(NO),在一定温度下,若使容器体积缩小到原来的1/2时,问反应速率如何变化?解:v=kc(H2)c2(NO)v2=k2c(H2)[2c(NO)]2=8v反应速率将为原速率得8倍。12.某基元反应A+BC,在1.20L溶液中,当A为4.0mol,B为3.0mol时,v为0.0042molL1s1,计算该反应的速率常数,并写出该反应的速率方程式。解:v=kcAcBk=0.0042moldm3s1/[(4.0mol/1.20dm3)(3.0mol)/1.20dm3]=3.5104mol1dm3s113.已知反应HI(g)+CH3(g)CH4+I2(g)在157oC时的反应速率常数k=1.7×10-5L·mol-1·s-1,在227oC时的速率常数k=4.0×10-5L·mol-1·s-1,求该反应的活化能。解:由ln21kk=21a11TTRE得)50014301(314.8100.4107.1ln55aEEa=21.85kJmol114.某病人发烧至40℃时,使体内某一酶催化反应的速率常数增大为正常体温(37℃)的1.25倍,求该酶催化反应的活化能?解:K3131K3101KmolkJ108.31425.11ln113-aEEa=60.0kJmol115.某二级反应,其在不同温度下的反应速率常数如下:T/K645675715750k103/mol1Lmin16.1522.077.5250(1)作lnk1/T图计算反应活化能Ea;(2)计算700K时的反应速率常数k。解:(1)画图略,Ea=140kJmol1;(2))71517001(314.8104.11055.7ln54k4104.56kmol1Lmin116.写出下列各化学反应的平衡常数K表达式:1)HAc(aq)H+(aq)+Ac(aq)2)Cu2+(aq)+4NH3(aq)Cu(NH3)4(aq)3)C(s)+H2O(g)CO(g)+H2(g)4)AgCl(s)Ag(aq)+Cl(aq)5)CaCO3(s)CaO(s)+CO2(g)6)2MnO4(aq)+5SO32(aq)+6H(aq)2Mn2(aq)+5SO42(aq)+3H2O(l)解:1)K=(c(H+)/c)(c(Ac)/c)(c(HAc)/c)12)K=(c(Cu(NH3)4/c(c(Cu2+)/c)1(c(NH3)/c)43)K=(p(CO)/p)(p(H2)/p)(p(H2O)/p)14)K=(c(Ag+)/c)(c(Cl)/c)5)K=p(CO2)/p6)K=(c(Mn+2)/c)2(c(SO42)/c)5(c(MnO41)/c)2(c(SO32)/c)5(c(H+)/c)617.已知下列化学反应在298.15K时的平衡常数:(1)2N2(g)+O2(g)2N2O(g);K1=4.81037(2)N2(g)+2O2(g)2NO2(g);K2=8.81019计算反应2N2O(g)+3O2(g)4NO2(g)的平衡常数K。解:(2)×2-(1)为所求反应:6110841088372191223../).(K/)K(K.18.已知下列反应在298.15K的平衡常数:1)SnO2(s