Chapter14-Electromotive Force

Ex1-pg441

In [1]:
import math
##Intitalisation of variables

T= 25. ##C
E= 0.0455 ##volt
r= 3.38*10**-4 ##volt degree^-1
F= 96500.
r1= 0.2390
##CALCULATIONS
dH= -F*r1*(E-(273.+T)*r)
##RESULTS
print'%s %.2f %s'% ('Enthalpy = ',dH,' calories ') 

Enthalpy =  1273.66  calories

Ex2-pg450

In [2]:
import math
##Intitalisation of variables
emf= 1.094 ##volt
e1= 0.334 ##volt
##CALCULATIONS
Ezn= (emf-e1)
##RESULTS
print'%s %.2f %s'% ('Ezn = ',Ezn,' volt ') 

Ezn =  0.76  volt

Ex3-pg454

In [3]:
import math
##Intitalisation of variables

emf= 0.0455 ##volt
T= 25. ##C
c= 0.1 ##N
emf1= 0.334 ##volt
emf2= 0.799 ##volt
k= 0.05915
##CALCULATIONS
ag= 10**((-emf2+(emf1-emf))/k)
##RESULTS
print'%s %.2e %s'% ('aAg+ = ',ag,' g ion per 1000 grams per litre ') 

aAg+ =  2.34e-09  g ion per 1000 grams per litre

Ex4-pg455

In [4]:
import math
##Intitalisation of variables
k= 0.059
e= -0.401 ##volt
c1= 10**-14 ## g ion per litre
c2= 10**-7 ## g ion per litre
##CALCULATIONS
E1= e+k*math.log10(c1)
E2= e+k*math.log10(c2)
##RESULTS
print'%s %.2f %s'% ('oxidation potential = ',E1,' volt ') 
print'%s %.2f %s'% ('\n oxidation potential = ',E2,' volt ') 

oxidation potential =  -1.23  volt 

 oxidation potential =  -0.81  volt

Ex6-pg464

In [5]:
import math
##Intitalisation of variables

e= 0.761 ##volt
e1= -0.34 ##volt
k= 0.02958 ##volt
##CALCULATIONS
r= 10**((e-e1)/k)
##RESULTS
print'%s %.2e %s'% ('K for the reaction =   ',r,'') 

K for the reaction =    1.66e+37

Ex7-pg468

In [10]:
import math
##Intitalisation of variables
c1= 0.1 ##M
c2= 0.01 ##M
k= 0.05915 ##volt
t1= 0.172
t2= 0.828 
##CALCULATIONS
El= (t1-t2)*k*math.log10(c2/c1)
##RESULTS
print'%s %.3f %s'% ('Liquid junction potential = ',El,'') 

Liquid junction potential =  0.039

Ex8-pg472

In [9]:
import math
##Intitalisation of variable
k= 0.05915 ##volt
n= 2. ##moles
c= 0.1 ##M
c1= 1. ##M
##CALCULATIONS
r= k*math.log10(c/c1)/n
##RESULTS
print'%s %.2f %s'% ('EMF = ',r,' volt ') 

EMF =  -0.03  volt

Ex9-pg477

In [8]:
import math
##Intitalisation of variables
e1= 0.31 ##volt
e2= 0.78 ##volt
##CALCULATIONS
e= e1+e2
##RESULTS
print'%s %.2f %s'% ('Decomposition voltage =   ',e,'') 

Decomposition voltage =    1.09

Ex10-pg478

In [7]:
import math
##Intitalisation of variables
k= 0.059 ##volt
c= 10**-7 ##M
e= 2.71 ##volt
c1= 6 ##M
e1= -0.4 ##volt
e2= -1.36 ##volt
e3= 0.6 ##volt
##CALCULATIONS
E1= -math.log10(c)*k
E2= e-k*math.log10(c1)
E3= e1+k*math.log10(c)
E4= e2+k*math.log10(c1)
E5= E3-e3
##RESULTS
print'%s %.2f %s'% ('EH = ',E1,' volt ') 
print'%s %.2f %s'% ('\n ENa = ',E2,' volt ') 
print'%s %.2f %s'% ('\n EO = ',E3,' volt ') 
print'%s %.2f %s'% ('\n ECl = ',E4,' volt ') 
print'%s %.2f %s'% ('\n Oxygen evolution potential = ',E5,' volt ') 

EH =  0.41  volt 

 ENa =  2.66  volt 

 EO =  -0.81  volt 

 ECl =  -1.31  volt 

 Oxygen evolution potential =  -1.41  volt