Zn and Cd metals do not show variable valency because : — d and f Block Elements Chemistry Question

💡 Solution & Explanation

Step 1: The Group 12 elements (Zn, Cd) possess a stable pseudo-noble gas configuration with a completed (n - 1)d10 subshell. Step 2: Removing electrons from a completely filled d-orbital requires a prohibitively high amount of energy, restricting their chemical activity. Step 3: Only the two s-electrons from the outermost shell participate in reactions, leading strictly to a stable +2 oxidation state. Thus, their completely filled d-subshells prevent variable valency, corresponding to option (b).