Question

Name the four quantum numbers and explain them
Tell how to find them​

Answer 1

✻ Quantum Numbers ✻

1) Principal quantum number

2) Azimuthal quantum number

3) Magnetic quantum number

4) Spin quantum number

✻ Principal quantum number (n)✻

Principal quantum number can be found by finding at which orbital it is present. For example :-

Consider the element Sodium.

Its electronic configuration can be written as :

Na - 1$s^2$ 2$s^2$ 2$p^6$ 3$s^1$

Here, the number present in the last shell will be the principal quantum number.

Thus, Principal quantum number for sodium is 3.

✻ Azimuthal quantum number (l)✻

Let us consider the same example sodium.

Azimuthal quantum number can be found out by seeing in which orbital it is present.

s - Azimuthal quantum number is 0

p - Azimuthal quantum number is 1

d - Azimuthal quantum number is 2

f - Azimuthal quantum number is 3

Sodium, last orbital is s. So, its Azimuthal quantum number wil be 0.

✻ Magnetic quantum number (m)✻

Magnetic quantum number can be any number between +l and -l. That is ranging from positive of Azimuthal quantum number to negative of it.

Here,in the case of sodium, only one value exists i e 0.Thus, Magnetic quantum number of sodium is 0.

✻ Spin quantum number (s)✻

This quantum can have value on $-\frac{1}{2}$ and $+\frac{1}{2}$ . Thus cannot be determined by any method.