Hello Aspirant,

According to the question, the element belongs to 3D series.

Magnetic moment=[n(n+2)]^(1/2)

=4.92 BM

The element belongs to 8th Group, and it is Fe.

So, A belongs to Group 8 (VIIIb)

A is Fe.

Hope this answer helps you.

Feel free to ask more questions.

Have a good day!!

Hello

As per my understanding the concrned element is Fe (iron). (In its +3 staate (Fe3+) iron loses its last 3 electrons which ultimately results in the same magnetic moment as iron itself. Henc it is iron, group 8 of the periodic table. If you are not sure then just take out the magnetic moment of both iron and iron+3.