Bohr’s Atomic model explain many of the atomic phenomena. He postulated three fundamental laws to overcome the inconsistency in the Rutherford model.
Postulate 1:- Electrons can not occupy states at all energy levels. Electrons can occupy states at only certain discrete energy levels. When electron occupies a discrete energy level, it does not emit radiation and is said to be Stationary (or Non-radiating state).
Postulate 2:-When an electron moves from Higher energy state (E2) to lower energy state (E1).It emitts radiation at a frequency given by
f= (E2 – E1)/h.
where ‘h’ is the plank’s constant h= 6.62 X 10-34 Joules. E1 and E2 are Energies in Joules.
Postulate 3:- Any stationary state is determined by the condition that the angular momentum of the electron in this state is quantized and is a multiple of h/2π .
angular momentum = Integral multiple of h/2π .
mvr = nh/2π.
The total energy of electron in stationary state is Wn = (-13.6/n2 ) eV.
