Question

Write the significance of $4$ quantum numbers.

Answer 1

The principal quantum number, n, designates the principal electron shell. Because n describes the most probable distance of the electrons from the nucleus, the larger the number n is, the farther the electron is from the nucleus, the larger the size of the orbital, and the larger the atom is.

The orbital angular momentum quantum number l determines the shape of an orbital, and therefore the angular distribution. The number of angular nodes is equal to the value of the angular momentum quantum number l.

The magnetic quantum number $m_l$ determines the number of orbitals and their orientation within a subshell.

Unlike n, l, and $m_l$, the electron spin quantum number ms does not depend on another quantum number. It designates the direction of the electron spin and may have a spin of +1/2,-1/2.