Question:medium

Identify the ion having 4f\(^6\) electronic configuration.

Updated On: Nov 28, 2025

Gd\(^{3+}\)
Sm\(^{3+}\)
Sm\(^{2+}\)
Tb\(^{3+}\)

Questions Asked in WBJEE exam

In the following sequence of reactions, compound 'M' is:

\( \text{M} \xrightarrow{\text{CH}_3\text{MgBr}} \text{N} + \text{CH}_4 \uparrow \xrightarrow{\text{H}^+} \text{CH}_3\text{COCH}_2\text{COCH}_3 \)

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The equivalent weight of \(\text{Na}_2\text{S}_2\text{O}_3\) (Gram molecular weight = \(M\)) in the given reaction is:
\[\text{I}_2 + 2 \text{Na}_2\text{S}_2\text{O}_3 \rightarrow 2 \text{NaI} + \text{Na}_2\text{S}_4\text{O}_6\]

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The reactivity order of the following molecules towards SN1 reaction is:
Allyl chloride (I), Chlorobenzene (II), Ethyl chloride (III)

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