Question

Elements of which period, among the following, will not have f-subshell in its electronic configuration?

• A. $5^{th}$ period elements
• B. $4^{th}$ period elements
• C. $3^{rd}$ period elements
• D. $7^{th}$ period elements

Answer 1

The correct option is C $3^{rd}$ period elements

$5^{th}$, $4^{th}$ and $7^{th}$ period elements of periodic table have f - subshells in their electronic configuration due to their high atomic number and thus have high number of electrons in them. $3^{rd}$ period elements do not have f - orbitals as their electrons are completely exhausted in filling upto d orbitals.