Analyzing the general variation curve of metallic radii across a standard transition series (e.g., t — d and f Block Elements Chemistry Question

💡 Solution & Explanation

The atomic radii curve for $d$ -block elements is universally U-shaped. It drops heavily at the beginning (due to unshielded nuclear charge pulling the valence shell), stabilizes in the center (where added $d$ -electron shielding cancels nuclear proton addition), and tips upward slightly at the very end (where complete $d^{10}$ filling causes aggressive inter-electronic repulsions that push the $s$ -electrons outward).