JEE Main 2022 (28 Jul, Shift 2) Chemistry Q38: Which of…

Question

Which of the following pair is not isoelectronic species?

(At. no. Sm, 62; Er, 68; Yb, 70; Lu, 71; Eu, 63; Tb, 65; Tm, 69)

Accepted Answer

Options 1 and 4: $\mathrm{Sm^{2+}}$ and $\mathrm{Er^{3+}}$; $\mathrm{Tb^{2+}}$ and $\mathrm{Tm^{4+}}$

Answer

$\mathrm{Sm^{2+}}$ and $\mathrm{Er^{3+}}$

Answer

$\mathrm{Yb^{2+}}$ and $\mathrm{Lu^{3+}}$

Answer

$\mathrm{Eu^{2+}}$ and $\mathrm{Tb^{4+}}$

Answer

$\mathrm{Tb^{2+}}$ and $\mathrm{Tm^{4+}}$

JEE Main 28 July 2022, Shift 2, Chemistry Q38