What Did Bohr Contribute To The Model Of The Atom?
Bohr proposed his atomic model using the PLANCK’s QUANTUM THEORY and proposed that the electron, in the hydrogen atom, can only exist in certain permitted quantized energy levels. The postulates of his atomic theory are: I) Electron revolves in one of the circular orbits outside the nucleus. Each orbit has a fixed energy and a quantum number is assigned to it. Ii) Electron present in a particular orbit neither emits nor absorbs energy while moving in the same fixed orbits. The energy is emitted or absorbed only when an electron jumps from one orbit to another. Iii) When an electron jumps, the energy change E2 – E1= hv Energy is abosrbed when an electron jumps from inner orbit to outer orbit and energy is released when electron jumps from outer to inner orbit. Electron can revolve only in those orbits having a fixed angular momentum (mvr). The angular momentum of an orbit depends upon its quantum number. The electron is bound to remain in one of these orbits and not in between them. So
