Class 9 Chemistry Structure of The Atom Bohr’s Model of Atom

Bohr’s Model of Atom

  • According to Neil’s Bohr the electrons could revolve around the nucleus in only certain orbits known as discrete orbits of electrons, each orbit having different radii.


  • When an electron is revolving in a particular orbit around the nucleus the electron does not radiate energy.
  • Bohr’s model of an atom can be described as follows:-
  1. An atom is made up of three sub-atomic particles – protons, electrons, neutrons.
  2. The protons and neutrons are located in a small nucleus in the centre of the atom.
  3. The electrons revolve around the nucleus rapidly in fixed circular paths called energy levels or shells.
  4. There is limit in the number of electrons that each shell can hold. It is given by the formula 2n2, where n = orbit number or energy level index.
  5. Each energy level is associated with a fixed amount of energy.
  6. There is no change in the energy of the electrons as long as they keep revolving in the same energy level, and the atom remains stable.


A few energy levels in an atom

Share these Notes with your friends  

< Prev Next >

You can check our 5-step learning process