# Ch-1 : Physical properties of elements¶

## Page No.4 Example 1.1.¶

In :
from math import pi
epsilon=8.854*10**-12
h=6.62*10**-34 #planck's constant
m=9.1*10**-31 #mass of electron
q=1.6*10**-19 #charge of electron
for n in :
r1=(epsilon*(h**2)*(n**2))/(pi*m*(q**2)) #radius of 1st orbit for hydrogen
x1=r1*10**10  # in A.U
print "r1=%0.2f (A.U)"%x1

for n in :
r2=(epsilon*(h**2)*(n**2))/(pi*m*(q**2)) #radius of 2st orbit for hydrogen
x2=r2*10**10  # in A.U
print "r2=%0.2f (meters)"%x2

for n in :
r3=(epsilon*(h**2)*(n**2))/(pi*m*(q**2)) #radius of 3st orbit for hydrogen
x3=r3*10**10  # in A.U
print "r3=%0.2f (meters)"%x3

r1=0.53 (A.U)
r2=2.12 (meters)
r3=4.77 (meters)


## Page No. 6 Example 1.2.¶

In :
E1=-13.6# #energy of 10th state
E10=-13.6/10**2# #enery in the ground state
lamda=12400/(E10-E1)# #wavelength of emitted photon
print "Wavelenth of the emitted photon is =%0.2f (Armstrong)"%lamda

Wavelenth of the emitted photon is =920.97 (Armstrong)


## Page No. 6 Example 1.3.¶

In :
Einfinity=0 #energy of electron at infinite orbit
E2=-13.6/2**2 #energy of electron at second orbit
wavelength=12400/(Einfinity-E2) #wavelength limit
print "the wavelength limit = 12400 / Einfinity-E2 =%0.2f (A.U)"%wavelength

the wavelength limit = 12400 / Einfinity-E2 =3647.06 (A.U)