Question

Which element of $3d$ series exhibits maximum oxidation state?

Answer 1

Manganese exhibit the largest number of oxidation states. It shows the oxidation states $2+,+3,+4,+5,+6$ and $+7$. The reason is the maximum no. of unpaired $e^{-}s$ present in the outermost shell. i.e. ${3d}^9{4S}^2$.