Question

Which of the following lanthanoid ions is diamagnetic?

[At. no. $Ce=58,Sm=62,Eu=63,Yb=70$]

• A. $C{e}^{4+}$
• B. $S{m}^{2+}$
• C. $E{u}^{2+}$
• D. $Y{b}^{2+}$

Answer 1

Answer: (A), (D)

The correct options are
A $C{e}^{4+}$
D $Y{b}^{2+}$

$C{e}^{4+}$ and $Y{b}^{2+}$ ions are diamagnetic.

$C{e}^{4+}$ has an electronic configuration of $4f^0$.

$Y{b}^{2+}$ has an electronic configuration of $4f^{14}$.

Since no unpaired electron is present, the ions are diamagnetic.

Hence, options $A$ and $D$ are correct.