From the list given below, the number of lanthanides which exhibit +4 state in their oxides is Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy

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Aicharya · Accepted Answer

$\mathrm{Pr}, \mathrm{Nd}, \mathrm{Tb}$ and Dy exhibit +4 state in their oxides as they acquire configurations closer to stable $4 \mathrm{f}^{\circ}$ and $4 \mathrm{f}^7$ configurations. $$ \begin{aligned} & \mathrm{Pr}^{4+}=[\mathrm{Xe}] 4 \mathrm{f}^1, \mathrm{Nd}^{4+}=[\mathrm{Xe}] 4 \mathrm{f}^2, \mathrm{Pm}^{4+}=[\mathrm{Xe}] 4 \mathrm{f}^3 \ & \mathrm{Sm}^{4+}=[\mathrm{Xe}] 4 \mathrm{f}^4, \mathrm{Eu}^{4+}=[\mathrm{Xe}] 4 \mathrm{f}^5, \mathrm{Gd}^{4+}=[\mathrm{Xe}] 4 \mathrm{f}^6, \ & \mathrm{~Tb}^{4+}=[\mathrm{Xe}] 4 \mathrm{f}^7, \mathrm{Dy}^{4+}=[\mathrm{Xe}] 4 \mathrm{f}^6 . \end{aligned} $$ ^

From the list given below, the number of lanthanides which exhibit +4 state in their oxides is Pr, Nd, Pm,…

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