Question

Name a transition element which does not exhibit variable oxidation states.

Answer 1

$\text{Transition element which does not exhibit variable oxidation states}$

All the $d$-blocks elements exhibit various valency or have variable oxidation number. But scandium does not show because scandium has partially filled $d$-orbitals in the ground state.


In the case of scandium, the number of electrons in the $3d$ and $4s$ orbital is $1$ and $2$ respectively. Removing three electrons from its $d$ and $s$ orbital forms a very stable inert gas configuration. It loses $1$ electron from $d$ orbital and $2$ electrons from $s$ orbital to form a $S{c}^{3+}$ ion.