# Chapter 7:Quantum theorem and electronic structure of Atoms¶

## Example no:7.1,Page no:27¶

In :
#Variable declaration
lamda=522*10**-9 #wavelength, m
c=3*10**8 #speed of light in vacuum, m/s

#Calculation
v=c/lamda #frequency, Hz

#Result
print"The frequency of the wave is :%.2e"%v,"Hz"

The frequency of the wave is :5.75e+14 Hz


## Example no:7.2,Page no:280¶

In :
#Variable declaration
c=3*10**8 #speed of light in vacuum, m/s
h=6.63*10**-34 #planck's constant, J s
lamda1=5*10**-5 #wavelength, m
lamda2=5*10**-11 #wavelength, m

#Calculation
#(a)
E1=h*c/lamda1 #energy, J
#(b)
E2=h*c/lamda2 #energy, J

#Result
print"(a) the energy of the photon is :%.2e"%E1,"J"
print"(b) the energy of the photon is :%.2e"%E2,"J"

(a) the energy of the photon is :3.98e-21 J
(b) the energy of the photon is :3.98e-15 J


## Example no:7.3,Page no:281¶

In :
#Variable declaration
W=3.42*10**-19      #Work function of cesium in J
h=6.63*10**-34      #planck's constant in J.s
v2=10**15     #Freq for irridation in s-1

#Calculation
#part a
KE=0
#hv=KE+w
v=W/h
#part b
KE=h*v2-W

#Result
print"(a)Minimum frequency of light is %.2e"%v,"s**-1"
print"(b).Kinetic energy of ejected electron is",KE,"J"

(a)Minimum frequency of light is 5.16e+14 s**-1
(b).Kinetic energy of ejected electron is 3.21e-19 J


## Example no:7.4,Page no:287¶

In :
#Variable declaration
c=3*10**8 #speed of light in vacuum, m/s
h=6.63*10**-34 #planck's constant, J s
Rh=2.18*10**-18 #rydberg's constant, J
ni=5.0 #initial orbit
nf=2.0 #final orbit

#Calculation
deltaE=Rh*(1/ni**2-1/nf**2)
lamda=c*h/-deltaE

#Result
print"The wavelength of the photon is :",round(lamda*10**9),"nm"

The wavelength of the photon is : 434.0 nm


## Example no:7.5,Page no:291¶

In :
#Variable declaration
h=6.63*10**-34 #planck's constant, J s
m1=0.06 #mass, kg
u1=68.0 #speed, m/s
m2=9.1094*10**-31 #mass, kg
u2=68 #speed, m/s

#Calculation
# (a)
lamda1=h/(m1*u1) #wavelength, m
#(b)
lamda2=h/(m2*u2) #wavelength, m

#Result
print"The wavelength of the tennis ball is :",lamda1,"m"
print"The wavelength of the electron is :%.1e"%lamda2,"m"

The wavelength of the tennis ball is : 1.625e-34 m
The wavelength of the electron is :1.1e-05 m


## Example no:,7.7,Page no:299¶

In :
#Variable declaration
n=3    #Principal quantum no

#Calculation
#The possible values of l are 0,1,2
s=1    #One 3s orbital,n=3,l=0,ml=0
p=3    #Three p obitals
d=5    #five 'd' orbital
total=s+p+d

#Result
print"The total no of orbitals is:",total

The total no of orbitals is: 9


## Example no:7.9,Page no:306¶

In :
#Variable declaration
n=3    #Principal quantum number
l=[0,1,2]
n=[0,0,0]

#Calculation
print"Value of l \t\t No of orbitals(2l+1)"
print"--------------------------------------------"
total=0
for i in range(0,3):
n[i]=2*l[i]+1
print l[i],"\t\t\t\t",n[i]
total=n[i]+total
max=2*total

#Result
print"The maximum number of electrons that can reside is",max


Value of l 		 No of orbitals(2l+1)
--------------------------------------------
0 				1
1 				3
2 				5
The maximum number of electrons that can reside is 18