Chapter21 Surface Chemistry

Example 21.1, Page no.79

In [25]:
import math
#initialisation of variables
A=500.0 #cmˆ2
m=0.106 #mg
N=6*10*23 # molecules
M=284.0 #g moleˆ−1
d=0.85 #g/cmˆ3
#CALCULATIONS
A1=A*M/(N*m*10**-3) 
t= m*(10**-3)/((A*d)*(10**-6)) 
#RESULTS
A1=round(A1,1)
t=round(t,2)
print 'cross −sectional area =',A1,'cmˆ2'
print 'thcikness t of the film =',t,'* 10^-5 cm'

cross −sectional area = 970741.0 cmˆ2
thcikness t of the film = 0.25 * 10^-5 cm

Example 21.2, Page no.79

In [14]:
import math
#initialisation of variables
V=129 #ml gˆ−1 
N=6*10**23 # molecules 
A=16.2 #Aˆ2 
#CALCULATIONS 
SA=V*N*A/((22.4)*10**23 )
#RESULTS
SA=round(SA,1)
print 'Surface area per gram of gel =',SA,'* 10^10 mˆ2 gˆ−1'

Surface area per gram of gel = 559.8 * 10^10 mˆ2 gˆ−1