Zinc (), Cadmium (), and Mercury () are structurally situated in the d-block but are formally exclud — d and f Block Elements Chemistry Question

💡 Solution & Explanation

A true transition element must have incompletely filled $d$ -orbitals. Group 12 elements ($Zn, Cd, Hg$) have $d^{10}$ configurations in their ground state ($ns^2$) and their most stable $+2$ state ($ns^0$), lacking unpaired $d$ -electrons entirely.