Question

$Gd\left(64\right)$ has ___________ unpaired electrons with sum of spin is equal to _________.

• A. $7,3.5$
• B. $8.3$
• C. $6,3$
• D. $8,4$

Answer 1

The correct option is D $8,4$

Electronic configuration of $Gd\left(64\right)$: $4f^{7}5d^1$
So it have eight unpaired electron with $+\frac{1}{2}$ spin

So, sum of spin $=8\times \frac{1}{2}=4$