Question

In an atom, which has $2K,8L,18M$ and $2N$ electrons in the ground state. The total number of electrons having magnetic quantum number $m=0$ is:

• A. $6$
• B. $10$
• C. $7$
• D. $14$

Answer 1

Answer: (D)

$14$

The electronic configuration of an atom is:

$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}$

Since total number of orbitals are $7$

and there are $2$ electron in each orbitals

$7\left(2\right)=14$

This implies that $D$ is the correct option.