Discuss three basic postulates of Bohr's model of atom.

Explanation

Bohr.s Postulates
In order to explain the stability of the atom and its line spectra, Bohr gave a set of postulates.
1. An electron in an atom revolves in a circular orbit around the nucleus. The force of attraction between the electron and the nucleus provides the necessary centripetal force for the circular motion.
2. The electron can revolve in those orbits for which its orbital angular momentum is an integral multiple of `h//2pi`. The allowed orbits are given by
`m v r= (nh)/(2 pi)` ...(1)
where n is an integer and h is Planck.s constant. The integer n is known as the principal number and can take any integral value 1, 2, 3, .... The numerical value of h is `6.624xx10^(-34)` Js. This postulate is known as quantization of the angular momentum.
3. Electromagnetic radiation is emitted when the electron jumps from a higher orbit having energy `E_(n_(1))` to a lower orbit having `E_(n_(2))`. The frequency v of the emitted radiation is given as
`n=(E_(n_(2))-E_(n_(1)))/(h)` ...(2)
Eq. (2) represents the Bohr.s frequency condition.