What are quantum numbers and how to assign value

Quantum numbers is the set of 4 numbers to get the complete information about the electron. Here we will discuss about their significance.

What is Quantum number

Quantum number gives the complete information of electron. it tells about the location, energy, the type of orbital occupied, shape and orientation of the orbital.

Types of Quantum numbers

There are 4 types of quantum numbers as given below:

Principle Quantum Number

  1. It explains the main lines of a spectrum. It tells about the main shell in which the electron resides.
  2. This quantum number gives the approx. distance from the nucleus and energy of the shell.
  3. It gives the maximum number of electrons present in the shell 2n^2
  4. n is the symbol of principle quantum number.
  5. The values of n = 1,2,3,4,………..
  6. It is given by K,L,M,N ………..shell

Azimuthal or Subsidiary or angular momentum quantum number

  1. It explains the fine structure of the line spectrum.
  2. It represents the number of subshells in a given main shell.
  3. This quantum number tells about the relative energies of the subshells.
  4. It tells about the shapes of the orbitals.
  5. l is the symbol of this quantum number.
  6. For a particular value of n, l = 0 to n-1
  7. For l = 0 , s subshell, l = 1, p subshell, l = 2, d subshell, l = 3, f subshell

Magnetic Quantum number

  1. It explains the splitting of lines in a magnetic field.
  2. It gives the number of orbitals present in any subshell or number of orientations.
  3. m is the symbol of the magnetic quantum number.
  4. For a particular value of l, m = -1 to +1 including 0
  5. The values of m for s and d subshell are given below.
Values of Magnetic quantum number @basicsofchemistry

Spin Quantum number

  1. It explains the magnetic properties of the substances.
  2. It gives the direction of the electron spin that is clockwise or anticlockwise.
  3. s is the symbol of spin quantum number.
  4. The value of s may be +1/2 or -1/2

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