Question

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

• A. 12 and 4
• B. 12 and 5
• C. 16 and 4
• D. 16 and 5

Answer 1

The correct option is B 12 and 5

The electronic configuration of $[Cr,Z=24]$:

$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{1}3d^5$.

The number of electrons with the azimuthal quantum numbers,

$l=1$ (number of p electrons) $=12$, and

$l=2$ (number of d electrons) $=5$.