文档介绍：Chapter 12
ponent Phase Equilibrium
Physical Chemistry
ponent Phase
1
ponent solid-liquid equilibrium
Freezing points of B & C
Curve AFGE
solid B+solid C
S
K
H
F
R
liquid solution (.) of B+C
G
E
D
T1
T2
T3
T
xB
.+B(s)
.+C(s)
0
1
I
Fig.
A
Freezing-point-depression curve of C due to solute B
Curve DE
Freezing-point-depression curve of B due to solute C
Point E
The eutectic point
T3
The eutectic temperature
Liquid-phase miscibility and solid-phase immiscibility
Simple eutectic system
Physical Chemistry
ponent Phase
2
Cd-Bi二元相图
Physical Chemistry
ponent Phase
eutectic mixture
Pure Bi
Pure Cd
Example
eutectic point
3
二组分固态部分互熔,液态完全互溶系统的液固平衡相图
读图要点:
①点、线、区的含义
②对比二组分液态部分互溶系统的沸点-组成图
③理解三相平衡线的含义
CED
— s(A+B)+ s(A+B)+lE(A+B)
具有低共熔点的熔点-组成图
300
250
150
200
Sn(A)
Pb(B)
xB
l(A+B)
t/℃
l(A+B)
C
D
E
350
s(A+B)
+
s(A+B)
s(A+B)+ s(A+B)
s(A+B)
327
232
l(A+B)+ s(A+B)
G
F
Sn(A) - Pb(B)系统的熔点-组成图
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•
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•
•
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•
4
g(A+B)
H2O(A)
n-C4H9OH(B)
wB
wB
t/℃
120
100
60
80
l(A+B)
l(A+B)
P1=常数
wB=
l(A+B)
l(A+B)
G
F
C
E
D
g(A+B)
l (A+B)
g(A+B)
l (A+B)
•
•
•
•
•
•
300
250
150
200
Sn(A)
Pb(B)
xB
l(A+B)
t/℃
l(A+B)
C
D
E
350
s(A+B)
+
s(A+B)
s(A+B)+ s(A+B)
s(A+B)
327
232
l(A+B)+ s(A+B)
G
F
•
•
•
•
•
•
•
5
ponent solid-liquid equilibrium
Solid solutions
Liquid-phase miscibility and solid-phase miscibility
Interstitial solid solution
Substitutional solid solution
Formed by substances with atoms, molecules, or ions of similar size and structure.
Formed by substances with small atoms or molecules occupying interstices (holes) in the crystal structure of another substance.
Physical Chemistry
ponent Phase
6
ponent solid-liquid equilibrium
Liquid-