MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

A transition element is defined as an element that has an incompletely filled d-orbital in its ground state or in any of its common oxidation states. Cadmium ( Cd ) belongs to group 12 and has the ground state electronic configuration [ Kr ] 4d^ 10 5s^ 2 . In its common oxidation state of +2, its configuration is [ Kr ] 4d^ 10 . Since the d-orbitals are completely filled in both its ground state and its stable oxidation state, Cd is not regarded as a transition element. Copper ( Cu ) and Gold ( Au ) have incompletely filled d-orbitals in their +2 and +3 oxidation states respectively, while Scandium ( Sc ) has an incompletely filled d-orbital in its ground state. Answer: Cd