NEET (UG) 2024 — Question 59

$\mathrm{E}_{\mathrm{Mn}^{3+} / \mathrm{Mn}^{2+}}^{\circ}>\mathrm{E}_{\mathrm{Cr}^{3+} / \mathrm{Cr}^{2+}}^{\circ}$ or $\mathrm{E}_{\mathrm{Fe}^{3+} / \mathrm{Fe}^{2+}}^{\circ}$

Electronic configuration of $\mathrm{Mn}^{3+}=[\mathrm{Ar}] 3 d^{4}$

Electronic configuration of $\mathrm{Mn}^{2+}=[\mathrm{Ar}] 3 d^{5}$

Electronic configuration of $\mathrm{Cr}^{3+}=[\mathrm{Ar}] 3 d^{3}$

Electronic configuration of $\mathrm{Cr}^{2+}=[\mathrm{Ar}] 3 d^{4}$

As $\mathrm{Mn}^{3+}$ from $d^{4}$ configuration goes to more stable $d^{5}$ configuration (Half filled), due to

more exchange energy in $d^{5}$ configuration.