Bohr Model of Hydrogen Atom

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 Bohr  Model of hydrogen Atom :


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https://youtu.be/uCL36h8wM5Y

In view of the limitations of the Rutherford atom model, Bohr cleverly combined classical ideas and early quantum concepts ( given by Planck ) to give what is  known as Bohr Model of hydrogen atom.

following are the  three basic postulates of this model :

  1. Every Atom consist of central core, called nucleus.  In which entire +ve charge and almost entire mass of the atom are concentrated. a suitable number of electron revolves  around the nucleus in circular orbit. the centripetal force required  for revolution is provided by electrostatic force of attraction between the electron and the nucleus. 
  2. According to Bohr electron can revolve only in certain discrete non radiating orbit called stationary orbit for  which total angular momentum of revolving electron (mvr) is an Integral multiple of h/2Ï€. where h  planck constant.
     3.  the emission or absorption of energy occurs  only where an electron jumps from on of its  specified non-radiating orbit to another . the difference in the total energy of the two stationary orbit is absorbed when the electron jumps from an inner to an outer orbit,  and emitted when electron jumps from  outer to inner orbit.

Limitations of Bohr theory :–

  1. this theory is only applicable to the simplest atom like H2. 
  2. Theory does not explain why orbit of electron taken as  circular, while elliptical orbit is also be possible. 
  3. this theory does not explain the fine structure of spectral line.  even in hydrogen atom. 

This is Shoaib Alam, Man behind your ElectronGate

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