Why does scandium show only +2 and +3 oxidation states?

1.	Why does scandium show only +2 and +3 oxidation states?
Answer» i. Scandium (Sc) has electronic configuration, Sc: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s² ii. Due to the loss of two electrons from the 4s-orbital, Sc acquires +2 oxidation state. Sc²⁺ : 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ iii. By the loss of one more electron from the 3d-orbital, it acquires +3 oxidation state. Sc³⁺ : 1s² 2s² 2p⁶ 3s² 3p⁶ iv. Since Sc³⁺ acquires extra stability of inert element [Ar], it does not form higher oxidation state.

Answer»

i. Scandium (Sc) has electronic configuration,

Sc: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s²

ii. Due to the loss of two electrons from the 4s-orbital, Sc acquires +2 oxidation state.

Sc²⁺ : 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹

iii. By the loss of one more electron from the 3d-orbital, it acquires +3 oxidation state.

Sc³⁺ : 1s² 2s² 2p⁶ 3s² 3p⁶

iv. Since Sc³⁺ acquires extra stability of inert element [Ar], it does not form higher oxidation state.

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