QJEEM23Ch3739: JEE Main 2023 Chemistry - Class 12 JEEM23Ch3739 Solution: Which of the following statements are correct? (A) The M /M…

The reduction electrode potential of $\mathrm{Mn}^{3+} / \mathrm{Mn}^{2+}$ is $+1.57 \mathrm{~V}$ while that of $\mathrm{Fe}^{3+} / \mathrm{Fe}^{2+}$ is $+0.77 \mathrm{~V}$ , hence $\mathrm{A}$ is wrong. Higher oxidation state of smaller $d$ -block elements is stabilized (or say form compounds) with smaller anion oxide that can be explained by stearic reason hence $B$ is correct.

The oxidation electrode potential of $\mathrm{Cr}^{2+} / \mathrm{Cr}^{3+}$ is $+0.41 \mathrm{~V}$ hence it can reduce $\mathrm{H}^{+}$ and so liberate $\mathrm{H}_2$ . The unpaired electrons in $\mathrm{V}^{2+}$ are 3 hence the magnetic moment of $\mathrm{V}^{2+}$ will be lesser than 4.4 BM.

Hence, only $B$ and $C$ are correct.