The quantum number which may be designated by $s$,$p$,$d$ and $f$ instead of numbers is

If the electronic configuration of a nitrogen atom were $1s^7$,its energy would be lower than the ground state configuration $1s^2 2s^2 2p^3$ because the electrons would be closer to the nucleus. However,the configuration $1s^7$ is not observed. Which of the following principles is violated?

What will be the maximum number of electrons in any atom having quantum numbers $n = 4, l = 2, m = -2$?

Which of the following is the correct set of $4$ quantum numbers for the $19^{th}$ electron in Chromium (Atomic number = $24$) in accordance with the Aufbau principle?

Write a note about the energy of orbitals in hydrogen.

Among the elements from atomic number $1$ to $36$,the number of elements which have an unpaired electron in their $s$-subshell is