1. Bohr postulates:
Bohr combined classical and early quantum concepts and gave his theory in the form of three postulates.
Electrons revolve round the positively charged nucleus in circular orbits.
The electron which remains in a privileged path cannot radiate its energy.
The orbital angular momentum of the electron is an integral multiple of h/2π.
Emission or Absorption of energy takes place when an electron jumps from one orbit to an other.
2. Negative sign implies that the electrons are strongly bounded to the nucleus.
3.
- rn = n2a0 = 5.3 × 10-11m
- r1 = a0 = 5.3 × 10-11m
- r2 = 4a0 = 21.2 × 10-11m
- r3 = 9a0 = 47.7 × 10-11m.