Question

State any two Bohr’s postulates and write the energy value of the ground state of the hydrogen atom. 

Answer 1

Bohr’s postulates

(1) Electrons revolve in only those orbits for which the angular momentum is an integral multiple of `h/(2pi)` .

`l = m"v"r = (nh)/(2pi)`

(2) When electrons jump from higher orbit to lower orbit they radiate energy in the form of `h"v"` , 

where h is the Planck’s constant and `"v"` is frequency `E_2 - E_1 = "hv"`

Energy of ground state 

`E = -13.6  eV`