Medium INTEGER +4 / -1 PYQ · JEE Mains 2022

The spin-only magnetic moment value of M3+ ion (in gaseous state) from the pairs Cr3+ / Cr2+, Mn3+ / Mn2+, Fe3+ / Fe2+ and Co3+ / Co2+ that has negative standard electrode potential, is ____________ B.M. [Nearest integer]

Answer (integer) 4

Solution

Among the pairs given, $\mathrm{Cr}^{3+} / \mathrm{Cr}^{2+}$ has negative reduction potential which is $-0.41 \mathrm{~V}$. <br/><br/> $\operatorname{Cr}$ (III) $\Rightarrow d^{3}$ <br/><br/> Number of unpaired electrons $=3$ <br/><br/> $\mu=\sqrt{3(3+2)}=\sqrt{15} \simeq 4$ B.M.

About this question

Subject: Chemistry · Chapter: Electrochemistry · Topic: Electrochemical Cells

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