There are four types of quantum numbers that specify the location and energy of an electron in an atom: principal quantum number (n), azimuthal quantum number (l), magnetic quantum number (m), and spin quantum number (s). The principal quantum number represents the main energy level of an electron. The azimuthal quantum number corresponds to electron subshells like s, p, d, and f. The magnetic quantum number specifies the spatial orientation of an electron, and the spin quantum number indicates the electron's spin direction.

1. QUANTUM NUMBERS
Jain Philo P.J
Assistant Professor
Department of Chemistry
St.Mary’s College, Thrissur

2. INTRODUCTION
Quantum numbers are a set of numbers which specify the location and energy of an
electron in an atom
Quantum Numbers ,Jain Philo P.J ,St Mary’s College

3. Quantum numbers are four types
Principle quntum number (n)
Azimuthal quantum number (l)
Magnetic quantum number (m)
Spin quantum number (s)
Quantum Numbers ,Jain Philo P.J ,St Mary’s College

4. Principal quantum number (n)
It specify the average distance of the electron from the nucleus
It represent the main energy level in which electron present
Positive integral value:1,2,3,……………………
Quantum Numbers ,Jain Philo P.J ,St Mary’s College

5. Azimuthal Quantum Number(l)
 Integral values from 0 to n-1
 l values of subshell
s subshell : 0
p subshell :1
d subshell :2
f subshell :3
Quantum Numbers ,Jain Philo P.J ,St Mary’s College

6. Magnetic quantum number (m)
• Spatial orientation of the electron in a magnetic field
• Total number of magnetic quantum number is 2l+1
• M value ranging from –l to +l
Quantum Numbers ,Jain Philo P.J ,St Mary’s College

7. Spin quantum number (s)
• Spin angular momentum of the electron and its orientation in space
• Two direction of spin for an electron
• Clockwise direction +1/2
• Anticlockwise direction -1/2
Quantum Numbers ,Jain Philo P.J ,St Mary’s College

8. Quantum number of last electron of sodium atom
• Subshell electronic configuration of sodium :1s2 ,2s 2p6 3s1
N=3,l=0,m=0,s=+1/2,-1/2
Quantum Numbers ,Jain Philo P.J ,St Mary’s College

9. REFERENCE
• Principles of inorganic chemistry :puri sharma kaliya
Quantum Numbers ,Jain Philo P.J ,St Mary’s College

10. THANK YOU