What are the postulates of Bohr's model of hydrogen atom?

Explanation

A. Postulates of Bohr.s theory:
1. Electrons revolve around the nucleus in certain, definite circular paths, called orbits. They are also known as energy levels or shells.
2. Each orit is associated with a definite amount of energy. Hence these orbits are called energy orbits or energy levels or energy shells.
3. As the value of n increass, the size and energ of the orbit increases.
4. As long as the electrons revolve in the circular orbits, they neither emit nor absorb energy. Hence these orbits are also called stationary orbits.
5. More than one stationary orbit is possible for any elctron and the angular momentum of the revolving electron is quantized. That is is electrons rvolve in those circular orbits in which the angular momentum of the revolving electron is an integral multiple of `h//2pi`
This can be expresssed as `mvr=nxxh/(2pi)`
where m=mass of the electron
`v=` velocity of the electron
r =radius of the orbit
h=Planck.s constant
n=Principal quantum number
6. The energy of electron changes when the electron jumps from one orbit to another orbit. When the electron jumps from a lower orbit to a higher orbit, energy is absorbed. Similarly when the electron jumps from a higher orbit to a lower orbit, energy is emitted. The energy emitted or absorbed is given by the equation `DeltaE=E_(2)-E_(1)=hv`
where
`E_(1)=` Energy of lower orbits
`E_(2)=` Energy of higher orbits
`DeltaE=` Difference in energy:
h=Planck.s constant:
v=Frequency.