Question

An element X belong to fourth period and fifteenth group of the periodic table, which one of the following is true regarding the outer electronic configuration of X?

• A. Partially filled $d-$orbtial and completely filled $s-$ orbital
• B. Completely filled $s-$ orbital and ocmpletely filled $p-$ orbitals
• C. Completely filled $s-$ orbital and half filled $p-$ orbitals
• D. Half filled $d-$ orbital s and completely filled $s-$ orbital

Answer 1

The correct option is C Completely filled $s-$ orbital and half filled $p-$ orbitals

For fifteenth group, the general outer electronic configuration is $n{s}^{2}n{p}^3.$
As the element is in $4^{th}$ period, the the elctronic configuration of X is $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^3.$
So, it has completely filled $s-$ orbital and half -filled $p-$ orbital.