Chemistry · d and f Block Elements

JEE Main 2025 — 4 April, Morning Shift — Question 5

Pair of transition metal ions having the same number of unpaired electrons is

Answer: A

\text{V}^{2+} \implies 3d^3 4s^0 \implies [\uparrow \downarrow] [\uparrow] [\ ] [\ ] [\ ] \implies 3 \text{ unpaired } e^-

\text{Co}^{2+} \implies 3d^7 4s^0 \implies [\uparrow \downarrow] [\uparrow \downarrow] [\uparrow] [\uparrow] [\uparrow] \implies 3 \text{ unpaired } e^-

\text{Ti}^{2+} \implies 3d^2 4s^0 \implies [\uparrow] [\uparrow] [\ ] [\ ] [\ ] \implies 2 \text{ unpaired } e^-

\text{Fe}^{3+} \implies 3d^5 4s^0 \implies [\uparrow] [\uparrow] [\uparrow] [\uparrow] [\uparrow] \implies 5 \text{ unpaired } e^-

\text{Cr}^{2+} \implies 3d^4 4s^0 \implies [\uparrow] [\uparrow] [\uparrow] [\uparrow] [\ ] \implies 4 \text{ unpaired } e^-

\text{Ti}^{3+} \implies 3d^1 4s^0 \implies [\uparrow] [\ ] [\ ] [\ ] [\ ] \implies 1 \text{ unpaired } e^-

\text{Mn}^{2+} \implies 3d^5 4s^0 \implies [\uparrow] [\uparrow] [\uparrow] [\uparrow] [\uparrow] \implies 5 \text{ unpaired } e^-

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Exam: JEE Main 2025
Paper: 4 April, Morning Shift
Subject: Chemistry
Chapter: d and f Block Elements
Topic: Properties of compounds of 3d Series elements + Comparison between 3d, 4d, 5d