Bohr’s atomic model
1913 Niels Bohr, proposes a new model, incorporating Planck’s discrete energies and Einstein’s photon
Bohr’s model accept Rutherford’s picture + new postulates
1. The angular momentum of the electron is quantized.
The possible angular momentum is given as:
Consequence: - restriction on the possible radii and speeds
(r1=5.3 x 10-11 m is the smallest radius, and n an integer
- the kinetic, potential and total energy of the electrons is also quantized
2. The electron does not radiate when it is on one of the allowed orbits
3. The atom can receive and emit only photons with well defined energies.
The energy of the photon equals the energy differences between the possible states of the electrons.
- emitting and absorbing photons