Number of colourless lanthanoid ions among the following is . Eu 3+ , Lu 3+ , Nd 3+ , La 3+ , Sm 3+

Chemistry · d and f Block Elements

JEE Main 2024 — 9 April, Shift 1 — Question 84

Number of colourless lanthanoid ions among the following is $\qquad$ .

$\mathrm{Eu}^{3+}, \mathrm{Lu}^{3+}, \mathrm{Nd}^{3+}, \mathrm{La}^{3+}, \mathrm{Sm}^{3+}$

Numerical answer — enter this value.

$\mathrm{La}^{+3}-[\mathrm{Xe}] 4 \mathrm{f}^{0}$

$\mathrm{Nd}^{+3}-[\mathrm{Xe}] 4 \mathrm{f}^{3}$

$\mathrm{Sm}^{+3}-[\mathrm{Xe}] 4 \mathrm{f}^{5}$

$\mathrm{Eu}^{+3}-[\mathrm{Xe}] 4 \mathrm{f}^{6}$

$\mathrm{Lu}^{+3}-[\mathrm{Xe}] 4 \mathrm{f}^{14}$

$\mathrm{La}^{+3}$ and $\mathrm{Lu}^{+3}$ do not show any colour because no unpaired electron is present.

Answer key and solution verified before publishing.

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