Chemistry - GENERAL CHEMISTRY Question with Solution | TestHub

Electronic configuration of Gd(64):$\left[\mathrm{X}\mathrm{e}\right]4{\mathrm{f}}^7,5{\mathrm{d}}^1,6{\mathrm{s}}^2$
So, total unpaired electrons$=8$
Sum of spin$=\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}=4$