What is oxidation state of Scandium?

1. Scandium$\left(\mathrm{Sc}\right)$ is a transition metal having atomic number 21.
2. Electronic Configuration is $\left[\mathrm{Ar}\right]3d^{1}4s^2$.
3. It is a d block element having one electron in its d orbital and two electrons in the s orbital. So it loses its outer three electrons due to this its oxidation state is$+3$.
4. On releasing two electrons from s orbital Scandium forms$+2$ an oxidation state. But it is very difficult to form a chemical species.
5. Sometimes Scandium forms $+1$ an oxidation state but it needs very high energy.