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Chemistry · 2026 · 1 mark
CBSE 2026 · Region 4 · Set 3 · Q16
Assertion (A): E_Mn^2+ / Mn^o value is highly negative. Reason (R): Because Mn^2+ is highly stable due to half-filled 3 d^5 configuration.
Assertion (A) : $\displaystyle \mathrm{E}_{\mathrm{Mn}^{2+} / \mathrm{Mn}}^{\mathrm{o}}$ value is highly negative.
Reason (R): Because $\displaystyle \mathrm{Mn}^{2+}$ is highly stable due to half-filled $\displaystyle 3 \mathrm{~d}^{5}$ configuration.
Official answer
(A)
Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
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