Medium MCQ +4 / -1 PYQ · JEE Mains 2025

The incorrect relationship in the following pairs in relation to ionisation enthalpies is :

  1. A $\mathrm{Mn}^{2+}<\mathrm{Fe}^{2+}$ Correct answer
  2. B $\mathrm{Mn}^{+}<\mathrm{Mn}^{2+}$
  3. C $\mathrm{Mn}^{+}<\mathrm{Cr}^{+}$
  4. D $\mathrm{Fe}^{2+}<\mathrm{Fe}^{3+}$

Solution

<p>$\mathrm{Mn}^{2+}:[\mathrm{Ar}] 3 \mathrm{~d}^5$</p> <p>Half filled stability</p> <p>More 1E than $\mathrm{Fe}^{2+}$</p> <p>$\mathrm{Fe}^{2+}:[\mathrm{Ar}] 3 \mathrm{~d}^6$</p>

About this question

Subject: Chemistry · Chapter: Periodic Table and Periodicity · Topic: Periodic Trends

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