3 3
He (0.04649 m ,283.2 K )
3,293.2 K )
H2 (0.02406 m
T
2
( 0.07055 m ,287.7 K ) ( 0.07055 m3,287.7 K )
V
2
S He nC V
,m
He ln
T
1
nR ln
V
1
所以:
287 .7
2 1 .5
0 .07055
-1
8 .314 ln
283 .2
-1
2 8. 314 ln
0 .04649
7 .328 J K
同理: ∴ΔS =
SH
2
8. 550 J K
SHe
+
S H
2
= 7.328 + 8.550 = 15.88 J · K
10. 解:
ΔH = ΔH1 + ΔH2 + ΔH3 = (75.4 × 10) - 6032 - (37.7 × 10) = - 5648.4 J
ΔS = ΔS1 + ΔSS3 = 75.4 2 + Δ
×
273 ln
263
6032
263 ln 273
- 1
- 273 + 37.7 ×
= - 20.66 J K·
ΔG = ΔH- TΔS = - 5648.4 + 263
p
l
(×- 20.66) = - 214.82 J
ln
p
ΔG≈ ΔG2 = - RT ×
s
p ln l
p
s
G RT
214 .82
p
l
= = 263 8.314
p
= 0.09824,
s
= 1.1032
11. 解: 用公式 ΔS = - R∑ni lnxi
- 1
= - 8.314 × (0.2 × ln0.2 + 0.5 × ln0.5 + 0.3 × ln0.3) = 8.561 J K ·
12.解:
- 1
ΔCp = 65.69 - 2 ×26.78 - 0.5 ×31.38 = - 3.56 J K· ΔHT = ∫ ΔCpdT + Const = - 3.65T + Const ,∵ T = 298K时, ΔH298 = - 30585J
代入,求得: Const = - 29524,ΔHT = - 3.65T - 29524,代入吉 -赫公式,
G
积分,
2
G 298
823
1
3 .65 29524
298
2
dT
66 .91
823 T
G
2
10836 .6
G
66 .91 30 .55
,
2
25143 J
823 298
恒温恒压下, ΔG > 0 ,反应不能自发进行,因此不是形成 13.解:
Ag2O 所致。