第第第第1111章章章章化学反应中的质量关系和能量关系化学反应中的质量关系和能量关系化学反应中的质量关系和能量关系化学反应中的质量关系和能量关系习题参考答案习题参考答案习题参考答案习题参考答案1.解:1.00吨氨气可制取2.47吨硝酸。2.解:氯气质量为2.9×103g。3.解:一瓶氧气可用天数33111-1222()(13.210-1.0110)kPa32L9.6d101.325kPa400LdnppVnpV−×××===××4.解:pVMpVTnRmR===318K44.9=℃5.解:根据道尔顿分压定律iinppn=p(N2)=7.6×104Pap(O2)=2.0×104Pap(Ar)=1×103Pa6.解:(1)2(CO)n=0.114mol;2(CO)p=42.8710Pa×(2)222(N)(O)(CO)pppp=−−43.7910Pa=×(3)4224(O)(CO)2.6710Pa0.2869.3310Panpnp×===×7.解:(1)p(H2)=95.43kPa(2)m(H2)=pVMRT=0.194g8.解:(1)ξ=5.0mol(2)ξ=2.5mol结论:反应进度(ξ)的值与选用反应式中的哪个物质的量的变化来进行计算无关,但与反应式的写法有关。9.解:∆U=Qp−p∆V=0.771kJ10.解:(1)V1=38.3×10-3m3=38.3L(2)T2=nRpV2=320K(3)−W=−(−p∆V)=−502J(4)∆U=Q+W=-758J(5)∆H=Qp=-1260J11.解::::NH3(g)+45O2(g)298.15K⎯⎯⎯⎯→标准态NO(g)+23H2O(g)�mrH∆=−226.2kJ·mol−112.解:mrH∆=Qp=−89.5kJmrU∆=mrH∆−∆nRT=−96.9kJ 解:(1)C(s)+O2(g)→CO2(g)�mrH∆=�mfH∆(CO2,g)=−393.509kJ·mol−121CO2(g)+21C(s)→CO(g)�mrH∆=86.229kJ·mol−1CO(g)+31Fe2O3(s)→32Fe(s)+CO2(g)�mrH∆=−8.3kJ·mol−1各反应�mrH∆之和�mrH∆=−315.6kJ·mol−1。(2)总反应方程式为23C(s)+O2(g)+31Fe2O3(s)→23CO2(g)+32Fe(s)�mrH∆=−315.5kJ·mol−1由上看出:(1)与(2)计算结果基本相等。所以可得出如下结论:反应的热效应只与反应的始、终态有关,而与反应的途径无关。14.解:�mrH∆(3)=�mrH∆(2)×3-�mrH∆(1)×2=−1266.47kJ·mol−115.解:(1)Qp=�mrH∆==4�mfH∆(Al2O3,s)-3�mfH∆(Fe3O4,s)=−3347.6kJ·mol−1(2)Q=−4141kJ·mol−116.解:(1)�mrH∆=151.1kJ·mol−1(2)�mrH∆=−905.47kJ·mol−1(3)�mrH∆=−71.7kJ·mol−117.解:�mrH∆=2�mfH∆(AgCl,s)+�mfH∆(H2O,l)−�mfH∆(Ag2O,s)−2�mfH∆(HCl,g)�mfH∆(AgCl,s)=−127.3kJ·mol−118.解:CH4(g)+2O2(g)→CO2(g)+2H2O(l)�mrH∆=�mfH∆(CO2,g)+2�mfH∆(H2O,l)−�mfH∆(CH4,g)=−890.36kJ·mo−1Qp=−3.69×104kJ 章化学反应的方向、速率和限度习题参考答案1.解:�mrH∆=−3347.6kJ·mol−1;�mrS∆=−216.64J·mol−1·K−1;�mrG∆=−3283.0kJ·mol−1<0该反应在298.15K及标准态下可自发向右进行。2.解:�mrG∆=113.4kJ·mol−1>0该反应在常温(298.15K)、标准态下不能自发进行。(2)�mrH∆=146.0kJ·mol−1;�mrS∆=110.45J·mol−1·K−1;�mrG∆=68.7kJ·mol−1>0该反应在700K、标准态下不能自发进行。3.解:�mrH∆=−70.81kJ·mol−1;�mrS∆=−43.2J·mol−1·K−1;�mrG∆=−43.9kJ·mol−1(2)由以上计算可知:�mrH∆(298.15K)=−70.81kJ·mol−1;�mrS∆(298.15K)=−43.2J·mol−1·K−1�mrG∆=�mrH∆−T·�mrS∆≤0T≥K)(298.15K)(298.15mrmr��SH∆∆=1639K4.解:(1)cK={}O)H()(CH)(H(CO)2432ccccpK={}O)H()(CH)(H(CO)2432pppp�K={}{}{}{}����pppppppp/O)H(/)(CH/)(H/(CO)2432(2)cK={}{})(NH)(H)(N3232212cccpK={}{})(NH)(H)(N3232212ppp�K={}{}���pppppp/)(NH/)(H/)(N3232212(3)cK=)(CO2cpK=)(CO2p�K=�pp/)(CO2(4)cK={}{}3232)(HO)(HccpK={}{}3232)(HO)(Hpp�K={}{}3232/)(H/O)(H��pppp5.解:设�mrH∆、�mrS∆基本上不随温度变化。�mrG∆=�mrH∆−T·�mrS∆�mrG∆(298.15K)=−233.60kJ·mol−1�mrG∆(298.15K)=−243.03kJ·mol−1 �Klg(298.15K)=40.92,故�K(298.15K)=8.3×1040�Klg(373.15K)=34.02,故�K(373.15K)=1.0×10346.解:(1)�mrG∆=2�mfG∆(NH3,g)=−32.90kJ·mol−1<0该反应在298.15K、标准态下能自发进行。(2)�Klg(298.15K)=5.76,�K(298.15K)=5.8×1057.解:(1)�mrG∆(l)=2�mfG∆(NO,g)=173.1kJ·mol−1�1lgK=RTG303.2)1(mf�∆−=−30.32,故�1K=4.8×10−31(2)�mrG∆(2)=2�mfG∆(N2O,g)=208.4kJ·mol−1�2lgK=RTG303.2)2(mf�∆−=−36.50,故�2K=3.2×10−37(3)�mrG∆(3)=2�mfG∆(NH3,g)=−32.90kJ·mol−1�3lgK=5.76,故�3K=5.8×105由以上计算看出:选择合成氨固氮反应最好。8.解:�mrG∆=�mfG∆(CO2,g)−�mfG∆(CO,g)−�mfG∆(NO,g)=−343.94kJ·mol−10,所以该反应从理论上讲是可行的。9.解:�mrH∆(298.15K)=�mfH∆(NO,g)=90.25kJ·mol−1�mrS∆(298.15K)=12.39J·mol−1·K−1�mrG∆(1573.15K)≈�mrH∆(298.15K)−1573.15�mrS∆(298.15K)=70759J·mol−1�Klg(1573.15K)=−2.349,�K(1573.15K)=4.48×10−310.解:H2(g)+I2(g)2HI(g)平衡分压/kPa2905.74−χ2905.74−χ2χ22)74.2905()2(xx−=55.3χ=2290.12p(HI)=2χkPa=4580.24kPan=pVRT=3.15mol11.解:p(CO)=1.01×105Pa,p(H2O)=2.02×105Pap(CO2)=1.01×105Pa,p(H2)=0.34×105PaCO(g)+H2O(g)→CO2(g)+H2(g)起始分压/105Pa1.012.021.010.34J=0.168,pK=1>0.168=J,故反应正向进行。12.解:(1)NH4HS(s)→NH3(g)+H2S(g)平衡分压/kPaxx �K={}{}/S)(H/)(NH23��pppp=0.070则x=0.26×100kPa=26kPa平衡时该气体混合物的总压为52kPa(2)T不变,�K不变。NH4HS(s)→NH3(g)+H2S(g)平衡分压/kPa25.3+yy�K={}{}//)25.3��pypy+(=0.070y=17kPa13.解:(1)PCl5(g)→PCl3(g)+Cl2(g)平衡浓度/(mol·L−1)0.250.070.0−0.250.00.250.0cK=)PCl()Cl()PCl(523ccc=0.62mol·L−1,α(PCl5)=71%PCl5(g)→PCl3(g)+Cl2(g)平衡分压0.20VRT0.5VRT0.5VRT�K={}{}{}���pppppp/)(PCl/)(Cl/)(PCl523=27.2(2)PCl5(g)→PCl3(g)+Cl2(g)新平衡浓度/(mol·L−1)0.10+y0.25−y0.25+y−210.0cK=)10.0()30.0)(25.0(yyy+−−mol·L−1=0.62mol·L−1(T不变,cK不变)y=0.01mol·L−1,α(PCl5)=68%(3)PCl5(g)→PCl3(g)+Cl2(g)平衡浓度/(mol·L−1)z−35.0z0.050+zcK=zzz−+35.0)050.0(=0.62mol·L−1z=0.24mol·L−1,α(PCl5)=68%比较(2)、(3)结果,说明最终浓度及转化率只与始、终态有关,与加入过程无关。14.解:N2(g)+3H2(g)→2NH3(g)平衡浓度/(mol·L−1)1.00.500.50cK={}{}32223)H()N()NH(ccc=21)L·mol(0.2−−若使N2的平衡浓度增加到1.2mol·L−1,设需从容器中取走x摩尔的H2。N2(g)+3H2(g)2NH3(g)新平衡浓度/(mol·L−1)1.20.50+(3×0.2)−x0.50−2×0.20 =2132)L·mol()02350.0(2.1)20.0250.0(−−−×+××−x=21)L·mol(0.2−−x=0.9415.解:(1)α(CO)=61.5%;(2)α(CO)=86.5%;(3)说明增加反应物中某一物质浓度可提高另一物质的转化率;增加反应物浓度,平衡向生成物方向移动。16.解:2NO(g)+O2(g)2NO2(g)平衡分压/kPa101−79.2=21.8286−79.2/2=24679.2�K(673K)={}{}{}���pppppp/)(O/(NO)/)(NO2222=5.36�mrG∆=�KRTlg303.2−,�mrG∆(673K)=−9.39kJ·mol−117.解:�mrG∆(298.15K)=−95278.54J·mol−1�mrG∆(298.15K)=�mrH∆(298.15K)−298.15K·�mrS∆(298.15K)�mrS∆(298.15K)=9.97J·mol−1·K−1,�mrG∆(500K)≈−97292J·mol−1�Klg(500K)=0.16,故)K500(�K=1.4×1010或者��12lnKK≈RH)K15.298(mr�∆⎟⎟⎠⎞⎜⎜⎝⎛−2112TTTT,�K(500K)=1.4×101018.解:因�mrG∆(