Chemistry - Complete d-block Question with Solution | TestHub

The electronic configuration $[Ar]3d^{5}4s^2$ belongs to Manganese (Mn). It possesses the maximum number of unpaired $3d$ electrons (5) and 2 valence $4s$ electrons. Because the energy gap between the $3d$ and $4s$ orbitals is very small, all 7 valence electrons can actively participate in bonding. This allows Manganese to exhibit the widest range of oxidation states in the $3d$ series, spanning from +2 to +7.