Question

Magnetic moment of $G{d}^{3+}$ ion (Z = 64) is

• A. 3.62 BM
• B. 9.72 BM
• C. 7.9 BM
• D. 10.60 BM

Answer 1

Answer: (C)

$Gd\left(64\right)=\left[Xe\right]4f^{7}5d^{1}6s^2$
$G{d}^{3+}=\left[Xe\right]4f^{7}5d^{0}6s^0$
i.e. no. of unpaired electrons $=7$
$\mu =\sqrt{n\left(n+2\right)}=\sqrt{7\left(7+2\right)}$
$=\sqrt{63}=7.93BM$