# Chapter 4-Electronic structures of atoms and molecules¶

## Ex1-pg76¶

In [2]:
import math
##Intitalisation of variables

v= 240. ##ml
p= 1.25 ##atm
p1= 0.75 ##atm
n= 2.
##CALCULATIONS
v1= v*p/p1
dv= v1-v
V= n*v1
##RESULTS
print'%s %.2f %s'% ('Increase in volume = ',dv,' ml')
print'%s %.2f %s'% ('\n Final volume = ',V,' ml')

Increase in volume =  160.00  ml

Final volume =  800.00  ml


## Ex2-pg78¶

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

v1= 360. ##ml
T1= 15. ##C
v2= 480. ##ml
##CALCULATIONS
T2= v2*(273.+T1)/v1
Tc= T2-273.
##RESULTS
print'%s %.2f %s'% ('Centigrade temperature = ',Tc,' C')

Centigrade temperature =  111.00  C


## Ex3-pg79¶

In [4]:
import math
##Intitalisation of variables

p1= 1.4 ##atm
v1= 250. ##ml
t1= 21. ##c
v2= 300. ##ml
t2= 49. ##c
##CALCULATIONS
p2= p1*v1*(273.+t2)/(v2*(273.+t1))
##RESULTS
print'%s %.2f %s'% ('Final pressure = ',p2,' atm')

Final pressure =  1.28  atm


## Ex4-pg82¶

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

v= 10. ##lit
p= 75. ##cm of hg
T= 27. ##C
R= 0.082 ##lit-atm/mole K
##CALCULATIONS
n= (p/76.)*v/((273.+T)*R)
##RESULTS
print'%s %.2f %s'% ('Moles of oxygen contained = ',n,' moles')

Moles of oxygen contained =  0.40  moles


## Ex5-pg84¶

In [18]:
import math
##Intitalisation of variables

T= 25. ##C
v= 190. ##ml
pt= 740. ##mm of hg
p1= 23.8 ##mm of hg
p2= 760. ##mm of hg
##CALCULATIONS
p= pt-p1
v= v*p/p2
##RESULTS
print'%s %.2f %s'% ('Partial pressure of dry gas = ',p,' mm')
print'%s %.2f %s'% ('\n volume of the dry gas = ',v,' ml')

Partial pressure of dry gas =  716.20  mm

volume of the dry gas =  179.05  ml


## Ex6-pg84¶

In [17]:
import math
##Intitalisation of variables

ma= 0.495 ##gm
Ma= 66. ##gms
mb= 0.182 ##gms
Mb= 45.5 ##gms
p= 76.2 ##cm of hg
##CALCULATIONS
na= ma/Ma
nb= mb/Mb
nt= na+nb
pa= p*na/nt
pb= p*nb/nt
##RESULTS
print'%s %.4f %s'% ('Number of moles of given gas A = ',na,'')
print'%s %.4f %s'% ('\n Number of moles of given gas B =  ',nb,'')
print'%s %.4f %s'% ('\n Total number of moles  = ',nt,'')
print'%s %.2f %s'% ('\n Partial pressure of A  = ',pa,' cm of mercury')
print'%s %.2f %s'% ('\n Partial pressure of B  = ',pb,' cm of mercury')

Number of moles of given gas A =  0.0075

Number of moles of given gas B =   0.0040

Total number of moles  =  0.0115

Partial pressure of A  =  49.70  cm of mercury

Partial pressure of B  =  26.50  cm of mercury


## Ex7-pg84¶

In [16]:
import math
##Intitalisation of variables

v1= 125. ##ml
p1= 0.6 ##atm
v2= 150. ##ml
p2= 0.8 ##atm
V= 500. ##ml
##CALCULATIONS
pa= p1*v1/V
pb= p2*v2/V
pt= pa+pb
##RESULTS
print'%s %.2f %s'% ('Partial pressure of A = ',pa,' atm')
print'%s %.2f %s'% ('\n Partial pressure of B = ',pb,' atm')
print'%s %.2f %s'% ('\n Total pressure of A = ',pt,' atm')

Partial pressure of A =  0.15  atm

Partial pressure of B =  0.24  atm

Total pressure of A =  0.39  atm


## Ex8-pg86¶

In [15]:
import math
##Intitalisation of variables

t1= 1.44 ##min
t2= 1.8 ##min
mo= 32. ##gms
mh= 2. ##gms
##CALCULATIONS
d2= (t1/t2)**2*(mo/mh)
##RESULTS
print'%s %.2f %s'% ('Approximate density of gas relative to hydrogen = ',d2,'')

Approximate density of gas relative to hydrogen =  10.24


## Ex9-pg92¶

In [14]:
import math
##Intitalisation of variables

T= 25. ##C
R= 8.31*10**7 ##ergs deg^-1 mole^-1
M= 32. ##gms
##CALCULATIONS
c= math.sqrt(3.*R*(273.+T)/M)
##RESULTS
print'%s %.2e %s'% ('Mean velocity of oxygen molecules = ',c,' cm sec^-1')

Mean velocity of oxygen molecules =  4.82e+04  cm sec^-1


## Ex10-pg96¶

In [13]:
import math
##Intitalisation of variables

n= 8.41*10**-5 ##poise
p= 1. ##atm
v= 22414. ##ml
m= 2. ##gms
T= 0. ##C
R= 8.31*10**7 ##ergs deg^-1 mole^-1
##CALCULATIONS
d= m/v
c= math.sqrt(8.*R*(273.+T)/(math.pi*m))
l= 3.*n/(d*c)
##RESULTS
print'%s %.2e %s'% ('Density of hydrogen gas = ',d,' gram cc^-1')
print'%s %.2e %s'% ('\n Mean velocity = ',c,' cm sec^-1')
print'%s %.2e %s'% ('\n Mean free path of the molecules = ',l,' cm')

Density of hydrogen gas =  8.92e-05  gram cc^-1

Mean velocity =  1.70e+05  cm sec^-1

Mean free path of the molecules =  1.66e-05  cm


## Ex11-pg97¶

In [12]:
import math
##Intitalisation of variables

t= 1. ##sec
v= 1. ##cc
T= 0. ##C
p= 1. ##atm
d= 8.9*10**-5 ##g cc^-1
n= 8.41*10**-5 ##poise
R= 8.31*10**7 ##ergs deg^-1 mole^-1
M= 4. ##gms
N= 6*10**23 ##molecules
n1= 2. ##moles
##CALCULATIONS
Z= M*(N/(v*22414.))*d*R*(273.+T)/(3.*math.pi*n1*n)
##RESULTS
print'%s %.2e %s'% ('Number of collisions = ',Z,' molecular collisions sec^-1 cc^-1')

Number of collisions =  1.36e+29  molecular collisions sec^-1 cc^-1


## Ex12-pg98¶

In [11]:
import math
##Intitalisation of variables

d= 8.9*10**-5 ##g cc^-1
R= 8.31*10**7 ##ergs deg^-1 mole^-1
N= 2.7*10**19 ##molecules
n= 8.41*10**-5 ##poise
T= 0. ##C
n1= 2. ##moles
##CALCULATIONS
s= math.sqrt(n1*d*math.sqrt(R*(273.+T)/(math.pi*n1))/(3.*math.pi*n*N))
##RESULTS
print'%s %.2e %s'% ('Collision diamter of hydrogen = ',s,' cm')

Collision diamter of hydrogen =  2.24e-08  cm


## Ex13-pg106¶

In [10]:
import math
##Intitalisation of variables

n= 4.
n1= 1.
n2= 1.5
R= 2. ##cal deg^-1 mole^-1
m=3.
##CALCULATIONS
Cv= ((3.*n-5.)+n1+n2)*R
Cv1= ((3.*n-6.)+2.*m*(n2-n1))*R
##RESULTS
print'%s %.2f %s'% ('Molar heat capacity of acetylene = ',Cv,' cal deg^-1 mole^-1')
print'%s %.2f %s'% ('\n Molar heat capacity of ammonia = ',Cv1,' cal deg^-1 mole^-1')

Molar heat capacity of acetylene =  19.00  cal deg^-1 mole^-1

Molar heat capacity of ammonia =  18.00  cal deg^-1 mole^-1


## Ex14-pg112¶

In [9]:
import math
##Intitalisation of variables
v= 1.32 ##lit
T= 48. ##C
p= 18.4 ##atm
R= 0.082 ##lit-atm deg^-1 mole^-1
a= 3.6
b= 4.28*10**-2
##CALCULATIONS
P1= R*(273.+T)/v
P2= (R*(273.+T)/(v-b))-(a/v**2)
##RESULTS
print'%s %.2f %s'% ('Pressure by ideal gas equation = ',P1,' atm')
print'%s %.2f %s'% ('\n Pressure by vander Waals equation = ',P2,' atm')

Pressure by ideal gas equation =  19.94  atm

Pressure by vander Waals equation =  18.54  atm


## Ex15-pg118¶

In [8]:
import math
##Intitalisation of variables

wa= 52.3 ##gms
wv= 52.96 ##gms
wb= 302. ##gms
T= 100. ##C
p= 752. ##mm
d= 1.29 ##g per litre
wa1= 0.32 ##gms
R= 0.082 ##lit-atm K^-1 mole^-1
v= 0.25 ##lit
##CALCULATIONS
W= wb-wa
Wv= wv-(wa-wa1)
M= Wv*R*(273.+T)/((p/760.)*v)
##RESULTS
print'%s %.2f %s'% ('Molecular weight of choloform = ',M,' gms')

Molecular weight of choloform =  121.17  gms


## Ex16-pg119¶

In [7]:
import math
##Intitalisation of variables

w= 0.241 ##gms
R= 0.082 ##lit-atm mole^-1 K^-1
T= 23. ##C
p= 764. ##mm
v= 47.9 ##ml of air
##CALCULATIONS
M= w*R*(273.+T)/((p/760.)*(v/1000.))
##RESULTS
print'%s %.2f %s'% ('Molecular weight of choloform = ',M,' gms')

Molecular weight of choloform =  121.48  gms


## Ex17-pg122¶

In [6]:
import math
##Intitalisation of variables

p= 795. ##mm
v= 0.501 ##lit
w= 1.35 ##gms
m= 92. ##gms
R= 0.082 ##lit-atm mole^-1 K^-1
T= 45. ##C
##CALCULATIONS
a= ((p/760.)*v/((w/m)*R*(273.+T)))-1.
##RESULTS
print'%s %.2f %s'% ('Fraction of N2O4 dissociated into NO2 = ',a,'')

Fraction of N2O4 dissociated into NO2 =  0.37