Chemistry - f-block Question with Solution | TestHub

Lanthanoid ion with no unpaired electron is diamagnetic in nature. $\begin{array}{ll}{\mathrm{Ce}}_{58}& =[\mathrm{Xe}]4f^{2}5d^{0}6s^2\\ C{e}^{2+}& =[\mathrm{Xe}]4f^2\text{ (two unpaired electrons) }\end{array}$ $\begin{array}{rl}{\mathrm{Sm}}_{62}& =[\mathrm{Xe}]4f^{6}5d^{0}6s^2\\ {\mathrm{Sm}}^{2+}& =[\mathrm{Xe}]4f^6(six\text{ unpaired electrons) }\\ {\mathrm{Eu}}_{63}& =[\mathrm{Xe}]4f^{7}5d^{0}6s^2\\ {\mathrm{Eu}}^{2+}& =[\mathrm{Xe}]4f^7\text{ (seven unpaired electrons) }\\ {\mathrm{Yb}}_{70}& =\left[{\mathrm{X}}_e\right]4f^{14}5d^{0}6s^2\\ {\mathrm{Yb}}^{2+}& =[\mathrm{Xe}]4f^{14}\text{ (no unpaired electrons) }\end{array}$ Because of the absence of unpaired electrons, ${\mathrm{Yb}}^{2+}$ is diamagnetic.