# how to calculate magnetic quantum number? explain clearly with an example

419 Points
11 years ago

Dear Student

The magnetic quantum number has values between -l and +l. When l =1, for example, m can have three values: -1, 0, and +1. Because you know  that the subshell designation for l =1 is "p", you now know that the p orbital has three components  px, py, and pz. Notice how the subscripts are related to a three-dimensional coordinate system, x, y, and z. The chart below shows a summary of the quantum numbers:

Principal Quantum Number (n) Azimuthal Quantum Number (l) Subshell Designation Magnetic Quantum Number (m) Number of orbitals in subshell
1 0 1s 0 1
2 0
1
2s
2p
0
-1 0 +1
1
3
3 0
1
2
3s
3p
3d
0
-1 0 +1
-2 -1 0 +1 +2
1
3
5
4 0
1
2
3
4s
4p
4d
4f
0
-1 0 +1
-2 -1 0 +1 +2
-3 -2 -1 0 +1 +2+3
1
3
5
7

All the best.

AKASH GOYAL

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SAGAR SINGH - IIT DELHI
879 Points
11 years ago

Dear student,

To describe the magnetic quantum number m you begin with an atomic electron's angular momentum, L, which is related to its quantum number $l\,$ by the following equation:

$\mathbf{L} = \hbar\sqrt{l(l+1)}$

where $\hbar = h/2\pi$ is the reduced planck constant.

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All the best.

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Sagar Singh

B.Tech, IIT Delhi

Aakash Dutta
29 Points
11 years ago

this is very simple