What is Bohr atomic model & how to explain hydrogen spectrum

Here we will discuss about Bohr atomic model. We will also study how to explain the hydrogen spectrum.

Bohr atomic model

Bohr’s model explained the drawbacks of Rutherford’s model of atom. The important postulates of this model of atom are:

  1. Electrons revolve around the nucleus in a particular orbit.
  2. Energy of each orbit is fixed. These are called as stationary orbits.
  3. The numbering to the orbits or shells are like K, L, M, N, ………etc
  4. Energy and radius of the orbit are as follows:

5. Like energy, angular momentum is also quantised.

6. Lowest energy state of the Hydrogen atom is the ground state of the atom.

7. When electron absorbs energy, it jumps from lower energy orbit to higher energy orbit.

8. When the electron jumps back to lower orbit, it releases energy.

9. Energy absorbed or released = E2 – E1

10. The main postulate of Bohr theory is quantisation of electronic energy.

Advantages of Bohr’s atomic model

  1. It explains the stability of the atom.
  2. It explains the Hydrogen spectrum.
  3. Bohr atomic model helps to calculate the energy of H atom or H like atom.
  4. It helps to find Rydberg’s formula.

Hydrogen spectrum

Electrons absorb energy and jump to different orbits. Then they start jumping back to inner orbits. Each jump releases energy . It appears in the form of line.

Limitations of Bohr atomic model

  1. It can not explain the line spectra of multielectron systems.
  2. This model is unable to explain splitting of lines in electric and magnetic field.
  3. It can not explain De-Broglie concept of dual nature.
  4. It is unable to explain Heisenberg’s uncertainty principle.
  5. This model can not explain 3 dimensional model of atom.

Check out the structure of NH3 here

For more updates join me on 

You Tube Channel :

Chemistry with mona mam

Website :

 Basics of chemistry.com

Facebook

Twitter
Quora
LinkedIn

Basics OF Chemistry
Author:

Let's Build chemistry with Chemistry !

Leave a comment