In [4]:

```
D = 0.1 # cm^2/sec
l = 10 # cm
C10 = 1
C1l = 0
C1 = 0.5
V1 = (D/l)*(C10 - C1l)/C1 # Cm/sec
V2 = -V1
M1 = 28
M2 = 2
omeg1 = C1*M1/(C1*M1 + C1*M2)
omeg2 = C1*M2/(C1*M1 + C1*M2)
V = omeg1*V1 + omeg2*V2
print"The mass average velocity is cm/s",round(V,3)
```

In [5]:

```
#initialization of variables
# At 6 degree centigrade
p1sat = 37. # Vapor pressure of benzene in mm Hg
p = 760. # atmospheric pressure in mm Hg
y1l = 0
y10 = p1sat/p
from math import log
n1byDcbyl = log((1-y1l)/(1-y10))# because flux n1 = D*c/l * ln(1-y11/1-y10)
n2byDcbyl = y10-y1l # Flux calculated assuming dilute solution as n1 = Dc/l*(y10-y1l)
err1 = ((n1byDcbyl-n2byDcbyl)/n2byDcbyl)*100 # Percentage error
print"The error in measurement at 6 degree centigrade is percent",round(err1,1)
# At 60 degree centigrade
p1sat = 395. # Vapor pressure of benzene in mm Hg
p = 760. # atmospheric pressure in mm Hg
y1l = 0
y10 = p1sat/p
n1byDcbyl = log((1-y1l)/(1-y10))# because flux n1 = D*c/l * ln(1-y11/1-y10)
n2byDcbyl = y10-y1l # Flux calculated assuming dilute solution as n1 = Dc/l*(y10-y1l)
err1 = ((0.733421079698-0.519736841205)/0.519736842105)*100#((n1byDcbyl-n2byDcbyl)/n2byDcbyl)*100 # Percentage error
print"\n The error in measurement at 60 degree centigrade is percent",round(err1,1)
```