(4)
12H2?g?+12Cl2?g?=HCl?g?;?rHm??92.30 kJ?mol
??1计算反应2NaCl?s?+H2SO4?l?=Na2SO4?s?+2HCl?g?在298 K时的?rHm和?rUm。
解
?rHm??rHm?3??2?rHm??????4??2?rHm?1???rHm?2????55.4 kJ?mol???1
?rUm??rHm?RT?n?g???rHm?2RT??50.4 kJ?mol?1
35. 已知反应：
H2?g?+?112O2?g?=H2O?l?;?rHm12??298 K???285.9 kJ?mol?1，水的气化热为
?2.445kJ?g，计算反应：H2?g?+解
O2?g?=H2O?g?的?rHm?298 K?。
?rHm(298 K)??rHm(H2O, l)??vapHm????(?285.9?18?2.445) kJ?mol?1?1
??242 kJ?mol
36. 已知反应：
(1) C?金刚石?+O2?g?=CO2?g?;?rHm?298 K???395.4 kJ?mol
??1(2) C?石墨?+O2?g?=CO2?g?;?rHm?298 K???393.5 kJ?mol
??1求C?石墨??C?金刚石?的?trsHm?298 K?。
?解 ?trHs?m??Hr?2??m??Hr??1m??1.9 kJ?m ol?137. 利用下列数据计算HCl?g?的生成焓。
?(1) NH3?aq,???HCl?aq,???NH4Cl?aq,??;?rHm?298 K???50.21 kJ?mol?1
(2) NH3?g?+H2O=NH3?aq,??;?rHm?298 K???35.561 kJ?mol
??1(3) HCl?g?+H2O=HCl?aq,??;?rHm?298 K???73.22 kJ?mol
??1(4) NH4Cl?s?+H2O=NH4Cl?aq,??;?rHm?298 K???16.32 kJ?mol
??1(5) (6) 解
1212N2?g?+2H2?g?+N2?g?+3212Cl2?g?=NH4Cl?s?;?rHm???298 K???313.8 kJ?mol?1
?1H2?g?=NH3?g?;?rHm?298 K???46.02 kJ?mol
?fHm?HCl,g???rHm?5???rHm?4???rHm?6???????rHm?1???rHm?2???rHm?3?
?????92.5 kJ?mol?138. 利用标准摩尔生成焓数据，计算下列反应的?rHm?298 K?。
?(1) Cl2?g?+2KI?s?=2KCl?s?+I2?s? (2) CO?g?+H2O?g?=CO2?g?+H2?g? (3) SO2?g?+12O2?g?+H2O?l?=H2SO4?l?
(4) CaCO3?s?=CaO?s?+CO2?g?
(5) CaO?s?+3C?石墨?=CaC2?s?+CO?g? (6) Fe2O3?s?+CO?g?=CO2?g?+2FeO?s? (7) 2H2S?g?+SO2?g?=3S?s?+2H2O?g? (8) 2Fe2O3?s?+3C?石墨?=4Fe?s?+3CO2?g? 解
(1) ?rHm(298 K)?2?fHm[KCl(s)]?2?fHm[KI(s)] ?[2?(?436.747)?2?(?327.9)] kJ?mol ??217.694 kJ?mol??1?1??
(2) ?rHm(298 K)??fHm[CO2(g)]??fHm[CO(g)]??fHm[H2O(g)] ?[?393.509?(?110.525)?(?241.818)] kJ?mol ??41.166 kJ?mol??1?1??
(3) ?rHm(298 K)??fHm[H2SO4(l)]??fHm[H2O(l)]??fHm[SO2(l)] ?[?813.989?(?285.83)?(?296.83)] kJ?mol ??231.329 kJ?mol????1
?1(4) ?rHm(298 K)??fHm[CaO(s)]??fHm[CO2(g)]??fHm[CaCO3(s)] ?[?635.09?(?393.51)?(?1206.87)] kJ?mol ?178.27 kJ?mol?1?1??
(5) ?rHm(298 K)??fHm[CaC2(s)]??fHm[CO(g)]??fHm[CaO(s)] ?[?59.8?(?110.525)?(?635.09)] kJ?mol ?464.765 kJ?mol?????1
?1(6) ?rHm(298 K)?2??fHm[FeO(s)]??fHm[CO2(g)]??fHm[Fe2O3(s)]??fHm[CO(g)] ?[2?(?272)?(?393.509)?(?110.525)?(?824.2)] kJ?mol ?2.784 kJ?mol?1?1???(7) ?rHm(298 K)?2??fHm[H2O(g)]?3??fHm[S(s)]??fHm[SO2(g)]?2??fHm[H2S(g)] ?[2?(?241.818)?(?296.83)?2?(?20.63)] kJ?mol ??166.176 kJ?mol??1?1????(8) ?rHm(298 K)?3??fHm[CO2(g)]?2??fHm[Fe2O3(s)] ?[3?(?393.509)?2?(?824.2)] kJ?mol ??467.873 kJ?mol?1?1?
39. 利用附录中的数据，计算下列反应的?rHm?298 K?。
?(1) C2H4?g?+H2?g?=C2H6?g? (2) 3C2H2?g?=C6H6?l? (3) C4H10?g?=C4H8?g?+H2?g? (4) C4H10?g?=C4H6?g?+2H2?g? 解
(1) ?rHm(298 K)??fHm[C2H6(g)]??fHm[C2H4(g)] ??84.68 kJ?mol?1???52.26 kJ?mol?1
??136.94 kJ?mol??1(2) ?rHm(298 K)??fHm(C6H6(l))?3??fHm(C2H2(g)) ?49.04 kJ?mol?1??3?(226.73 kJ?mol)
?1?1 ??631.15 kJ?mol?(3) ?rHm(298 K)??fHm[C4H8(g)]??fHm[C4H10(g)] ??0.13 kJ?mol?1??(?126.15 kJ?mol)
?1 ?126.02 kJ?mol??1(4) ?rHm(298 K)??fHm[C4H6(g)]??fHm[C4H10(g)] ?110.16 kJ?mol?1??(?134.52 kJ?mol)
?1?1 ?244.68 kJ?mol40. 已知C2H5OH?l?在25℃时的标准摩尔燃烧焓为-1367kJ?mol，试用CO2?g?和
?1H2O?l?在298 K时的生成焓，计算C2H5OH?l?在298 K时的标准摩尔生成焓。
解 查表得：
?fHm?CO2,g???393.514 kJ?mol,?fHm?H2O,l???285.84 kJ?mol。
???1?1C2H5OH?l?+3O2?g?=2CO2?g?+3H2O?l?
?cHm?C2H5OH,l??2?fHm?CO2,g??3?fHm?H2O,l???fHm?C2H5OH,l?
?????fHm?C2H5OH,l??2?fHm?CO2,g??3?fHm?H2O,l???cHm?C2H5OH,l???????275.4 kJ?mol?1
Pb?s?、41. 已知PbO?s?在291 K的摩尔生成焓为-219.5kJ?mol，在291 K至473 K之间，
?10.900和0.218J?gO2?g?及PbO?s?的平均热容各为0.134、473 K时的摩尔生成焓。 解 Pb?s?+??1?K?1，试计算PbO?s?在
12O2?g?=PbO?s?
??fHm?T2???fHm?T1???Cp?T2?T1?????219.5??0.218?223?0.134?207??12?0.9?32??10?1?3?182? kJ?mol
?1??218 kJ?mol42. 已知反应CO2?g??C?石墨??2CO?g?，在
?5?1293 K
?时的反应焓
?rHm?293 K???1.732?10kJ?mol，求该反应的?rHm?f?T?的关系式。所需
热容数据自行查表。 解 查得：
Cp,m?CO2,g???28.66?35.702?10?3TK?J?K?1?mol?1
?35Cp,m?C,石墨???17.15?4.27?10TK?8.79?10?KT??2?J?K?1?mol?1 ??35Cp,m?CO,g???26.5366?7.6831?10TK?0.46?10?KT??2?J?K?1?mol?1 ??Cp,m?2Cp,m?CO,g??Cp,m?石墨??Cp,m?CO2,g??35??7.2632?24.6058?10TK?7.87?10?KT??2?J?K?1?mol?1?