Solution

The last electron enters the 3d subshell, so this is a d-block (transition) element. This is vanadium (Z = 23).
For d-block elements, group number = number of (n–1)d electrons + number of ns electrons.
Group number $= 3 + 2 = 5$
So the element is placed in the fifth group (group 5).

Concept Group number of d-block element

Classification of Elements and Periodicity in Properties in past papers

41 questions from this chapter have appeared across 23 exam years.