Consider the ground state of $Cr$ $(Z = 24)$. The numbers of electrons with the azimuthal quantum numbers,$l = 1$ and $l = 2$ are,respectively:

The electrons,identified by quantum numbers $n$ and $l$ as $(i) n = 4, l = 1$,$(ii) n = 4, l = 0$,$(iii) n = 3, l = 2$,$(iv) n = 3, l = 1$,can be placed in order of increasing energy,from the lowest to highest,as:

The number of orbitals in $2p$ sub-shell is

How many orbitals are present in the $4^{th}$ shell with $\ell = 2$?

The Aufbau principle is obeyed in which of the following electronic configurations?

Which of the following sets of quantum numbers is not valid?