Question

What are the shortcomings of Rutherford model. How are these shortcomings was removed by Bohr in his model?

Answer 1

Answer:

They are: Rutherford's model was unable to explain the stability of an atom. According to Rutherford's postulate, electrons revolve at a very high speed around a nucleus of an atom in a fixed orbit. However, Maxwell explained accelerated charged particles release electromagnetic radiations.

Explanation:

Rutherford described the atom as consisting of a tiny positive mass surrounded by a cloud of negative electrons. Bohr thought that electrons orbited the nucleus in quantised orbits.

Bohr built upon Rutherford's model of the atom. In Rutherford's model most of the atom's mass is concentrated into the centre (what we now call the nucleus) and electrons surround the positive mass in something like a cloud.

Bohr's most significant contribution was the quantisation of the model. He believed that electrons moved around the nucleus in circular orbits with quantised potential and kinetic energies. So it was not possible for electrons to occupy just any energy level.

In principle the quantisation aspect of the model is still believed to be correct. The main problem lies in the idea of electrons in circular orbits. This does not satisfy the Heisenberg uncertainty principle, which is that it is not possible to know the position and momentum of a particle simultaneously.

Answer 2

Answer:

the Rutherford's atomic model explains the structure of an atom in a very simple way. But, it suffers from the following drawbacks:

• An electron revolving around the nucleus gets accelerated towards the nucleus. An accelerating charged particle must emit radiation and lose energy . Thus, the electrons in an atom must continuously emit radiation and lose energy .Because of this loss of energy of the electron would slow down and will not be able to withstand the attraction of the nucleus.As a result, the electron should follow a spiral path and ultimately fall into the nucleus. if it happens then the atom should collapse . But this does not happen atoms are stable this indicates that there is something wrong in rutherford's nuclear model of an atom.
• Rutherford's model of atom does not say anything about the arrangement of electrons in an atom.

Rutherford's nuclear model of atom although a great contribution to the science .But it could not explain certain observations. A brilliant description of atomic structure was proposed by Neil bohr in 1913.

• According to Neil bohr in an atom the electrons revolve around the nucleus in certain definite circular path called orbits of shells.
• Each shell corresponds to a definite energy. Therefore, these circular orbit are also known as energy level or energy shell.