Question

Give reason for the following statements:

Scandium (Z = 21) is a transition element but Zn (Z = 30) is not.

Answer 1

On the basis of incompletely filled 3d-orbitals in case of Scandium atom (3d¹) having one electron in its ground state, it is regarded as a transition element. On the other hand, zinc atom having completely filled d-orbitals (3d¹⁰) in its ground state as well as in its oxidized state, it is not considered as a transition element.