Question

Why $Sc(Z=21)$ is not considered as transition element?

• A. Properties of $Sc$ are similar to alkali metals
• B. $3d-$ orbitals are empty in its stable compound
• C. Stable oxidation number of $Sc$ is $+2$
• D. Atomic volume of $Sc$ is very large

Answer 1

Answer: (B)

Outer electronic configuration of $Sc$ is $3d^1,$ $4s^2$ In the stable oxidation state ie, +3, the electronic configuration of $+3$ is $S{c}^{3+}:1s^2,2s^{2}2p^6,3s^{2}3p^{6}3d^0$ It shows that 3d subshell is empty. Transition element can refer to those elements which form atleast one ion with a partially filled d shell of electrons. As $S{c}^{3+}$ has no electrons in its d orbital, hence, it is not considered as transition element in the stricter sense.