11-21
M=XAMA+XBMB
CB=XBC
VA=NA/CA
VB=NB/CB=0
V*=NA+NB
C=7.17 *10“3
V=nA+nB
=nA/
“
JA=CA(VA“V*)=NA“XANA=XBNA
(*105)
(*103)
z
XB
XA
CB
CA
ρΒ
ρA
ρ
ωΒ
ωA
ω
0
0.329
0.671
1.3
2.65
0.376
2.02
2.4
0.158
0.842
60.7
5
0.434
0.566
1.71
2.24
0.495
1.71
2.21
0.226
0.774
56
10
0.573
0.427
2.26
1.69
0.655
1.29
1.95
0.338
0.661
49.4
15
0.757
0.243
2.99
0.96
0.865
0.73
1.6
0.544
0.456
40.5
20
1
0
3.95
0
1.14
0
1.14
1
0
28.97
(*103)
(*106)
(*108)
z
VB
VA
V*
V
jA=-jB
JA=-JB
0
0
9.9
7.17
8.32
3.16
8.7
5
0
11.8
7.17
9.05
4.52
11.45
10
0
15.6
7.17
10.25
6.77
15.15
15
0
27.5
7.17
12.5
10.9
20
Mole fraction
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 5 10 15 20
Z (cm)
mole fraction
Diffusion Flux
0
5
10
15
20
25
30
0 5 10 15 20
Z (cm)
diffusion Flus(*10^6, *10^8)
mass/cm3-sec
P11-7 (e)
Evaporation Rate of CS2 (ρliq @ 20 oC = 1.26 gm/cc)
Q=nAA
“
liq
t=
(2.0 *10#5)(
$
4)(3600 * 24)
1.26
day
Ccm 03 20(@
075.1=
11-23
A
A AB
dC
W D
dt
=!
2
1
0
A
A
L C
A AB A C
W z D C=!
( )
1 2
AB
A A A
D
W C C
L
=!
Volume 2:
( )
10
A
A C
d C V
W A
dt =!
( )
1
1 2
1
C AB
A
A A
A D
dC C C
dt V L
=! !
( )
2
1 2
2
C AB
A
A A
A D
dC C C
dt V L
=!
Subtraction gives us:
( ) ( )
1 2
1 2
1 2
1 1
A A C AB
A A
d C C A D C C
dt L V V
!” #
=!+!
$ %
& ‘
Now integrate:
( )
1 2
1 2
1 1
ln Constant
C AB
A A
A D
C C t
L V V
! “
#=# # +
$ %
& ‘
P11-8 (b)
( )
1 2A A
C C k IC!=“
1 2
1 1
ln ln Constant
C AB
A D
k IC t
L V V
! “
+#=$ $ +
% &
‘ (
2
1 2
1 1
ln C
C AB
A D
IC t
L V V
! “
#=$ $ +
% &
‘ (
( ) 2
ln 0.01025 C
AB
IC D t!=“+
if we plot ln(ΔIC) as a function of time and find the slope, that would give us –DAB
See Polymath program P11-8-b.pol.
11-24
POLYMATH Results
Linear Regression Report
Model: lnDIC = a0 + a1*t
Variable Value 95% confidence
a0 3.7024708 0.0078035
a1 -0.0107008 9.83E-05
General
Statistics
R^2 = 0.9998944
Rmsd = 0.0015013
Variance = 2.608E-05
P11-9
11-25
P11-10 (a)
11-26
P11-10 (b)
11-28
P11-10 (d)
P11-11 (a)
11-29
11-30
P11-11 (b)
11-31
11-32
P11-11 (c)
11-33
P10-12 (a)
11-34
11-35
P10-12 (b)
11-36
P10-12 (c)
11-37
P10-12 (d)
The plot of the data is shown below
11-38
P11-14
11-39
CDP11-B
CDP11-C
CDP11-D
CDP11-E
CDP11-F
CDP11-G
CDP11-H
11-40
CDP11-I
CDP11-J
CDP11-K
CDP11-L
CDP11-M