第1章 化学反应中的质量关系和能量关系 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2.9×10g 3.解:一瓶氧气可用天数
n1(p?p1)V1(13.2?103-1.01?103)kPa?32L ???9.6d
n2p2V2101.325kPa?400L ? d-13
4.解:T?pVMpV? nRmR = 318 K ?44.9℃ 5.解:根据道尔顿分压定律
pi?p(N2) = 7.6?104 Pa p(O2) = 2.0?104 Pa p(Ar) =1?103 Pa
nip n6.解:(1)n(CO2)? 0.114mol; p(CO2)? 2.87 ? 104 Pa
(2)p(N2)?p?p(O2)?p(CO2)?3.79?104Pa n(O2)p(CO2)2.67?104Pa (3)???0.286
np9.33?104Pa7.解:(1)p(H2) =95.43 kPa (2)m(H2) =
pVM = 0.194 g RT8.解:(1)? = 5.0 mol
(2)? = 2.5 mol
结论: 反应进度(?)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 = 0.771 kJ 10.解: (1)V1 = 38.3?10 m= 38.3L
(2) T2 =
-3
3
pV2= 320 K nR(3)?W = ? (?p?V) = ?502 J (4) ?U = Q + W = -758 J (5) ?H = Qp = -1260 J
11.解:NH3(g) +
531?298.15K??NO(g) + H2O(g) ?rHm= ? 226.2 kJ·mol? O2(g) ???标准态4212.解:?rHm= Qp = ?89.5 kJ ?rUm= ?rHm? ?nRT
= ?96.9 kJ
13.解:(1)C (s) + O2 (g) → CO2 (g)
?rHm = ?fHm(CO2, g) = ?393.509 kJ·mol?
??1
11CO2(g) + C(s) → CO(g) 221??rHm = 86.229 kJ·mol?
CO(g) +
?12Fe2O3(s) → Fe(s) + CO2(g) 331
?rHm = ?8.3 kJ·mol?
各反应?rHm之和?rHm= ?315.6 kJ·mol?。
??1
(2)总反应方程式为
3C(s) + O2(g) + 1Fe2O3(s) → 3CO2(g) + 2Fe(s)
23231??rHm = ?315.5 kJ·mol?
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:?rHm(3)=?rHm(2)×3-?rHm(1)×2=?1266.47 kJ·mol?
???1
???15.解:(1)Qp =?rHm== 4?fHm(Al2O3, s) -3?fHm(Fe3O4, s) =?3347.6 kJ·mol?
1
(2)Q = ?4141 kJ·mol?
1
???16.解:(1)?rHm =151.1 kJ·mol?(2)?rHm = ?905.47 kJ·mol?(3)?rHm =?71.7
1
1
kJ·mol?
1
?????17.解:?rHm=2?fHm(AgCl, s)+?fHm(H2O, l)??fHm(Ag2O, s)?2?fHm(HCl, g) ? ?fHm(AgCl, s) = ?127.3 kJ·mol?
1
18.解:CH4(g) + 2O2(g) → CO2(g) + 2H2O(l)
???? ?rHm = ?fHm(CO2, g) + 2?fHm(H2O, l) ??fHm(CH4, g)
= ?890.36 kJ·mo ?
1
Qp = ?3.69?10kJ
4
第2章 化学反应的方向、速率和限度
??1.解:?rHm = ?3347.6 kJ·mol?;?rSm = ?216.64 J·mol?·K?;?rGm = ?3283.0
1
?11
kJ·mol?< 0
1
该反应在298.15K及标准态下可自发向右进行。
?2.解: ?rGm = 113.4 kJ·mol? > 0
1
该反应在常温(298.15 K)、标准态下不能自发进行。
?? (2)?rHm = 146.0 kJ·mol?;?rSm = 110.45 J·mol?·K?;?rGm = 68.7 kJ·mol?
1
?111
> 0
该反应在700 K、标准态下不能自发进行。
??3.解:?rHm = ?70.81 kJ·mol? ;?rSm = ?43.2 J·mol?·K?;?rGm = ?43.9 kJ·mol?
1
?111
(2)由以上计算可知:
?? ?rHm(298.15 K) = ?70.81 kJ·mol?;?rSm(298.15 K) = ?43.2 J·mol?·K?
1
1
1
?? ?rGm = ?rHm ? T ·?rSm ≤ 0
? T ≥
??rHm(298.15 K)??rSm(298.15 K) = 1639 K
3p (CO) ? p (H2) ?c (CO) ? c (H2) ?4.解:(1)Kc = Kp =
p (CH4) p (H2O)c (CH4) c (H2O)3 K?
?p (CO) / p?? p (H) / p ? =
?p (CH)/p?? p (HO) / p???32??42 (2)Kc =
?c (N2)?? c (H2) ?c (NH3) 12 32 Kp =
2)/??p (N2)?? p (H2) ?p (NH3) 12 32
K? =
?p (N2)/1?2p ?? p (Hp ??32p (NH3) /p
(3)Kc =c (CO2) Kp =p (CO2) K? =p (CO2)/p? (4)Kc = K?
? c (H2O) ? ? c (H2) ?33 Kp =
? p (H2O) ? ? p (H2) ?33
?=
? p (H p (H2O)/p? 2)/p?? ?33
??5.解:设?rHm、?rSm基本上不随温度变化。
????rGm = ?rHm ? T ·?rSm
1??rGm(298.15 K) = ?233.60 kJ·mol? 1??rGm(298.15 K) = ?243.03 kJ·mol?
lgK?(298.15 K) = 40.92, 故 K?(298.15 K) = 8.3?1040 lgK?(373.15 K) = 34.02,故 K?(373.15 K) = 1.0?1034
??6.解:(1) ?rGm=2?fGm(NH3, g) = ?32.90 kJ·mol? <0
1
该反应在298.15 K、标准态下能自发进行。
(2) lgK?(298.15 K) = 5.76, K?(298.15 K) = 5.8?10
5
??7. 解:(1) ?rGm(l) = 2?fGm(NO, g) = 173.1 kJ·mol?
1
lg?K1=
???fGm(1)31? = ?30.32, 故 K1= 4.8?10?
2.303 RT