ChemistryNEET 2021Electronic configuration, Aufbau, Pauli, Hund

Structure of Atom

From the following pairs of ions, which one is not an isoelectronic pair?

A. $O^{2 -}, F^{-}$
B. $N a^{+}, M g^{2 +}$
C. $M n^{2 +}, F e^{3 +}$
D. $F e^{2 +}, M n^{2 +}$ ✓

You have the answer. The worked solution — and why the other three were written — is part of a paid pack.

More from this chapter in past papers

Select the correct statements from the following: A. Atoms of all elements are composed…NEET 2023
The number of protons, neutrons and electrons in ^{175} {71} {Lu}, respectively, are:NEET 2020
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From Chemistry › Structure of Atom › Electronic configuration, Aufbau, Pauli, Hund — lectures, notes and every past question on it.

Last revised 7 Sept 2026. Found a mistake? Tell us — corrections are the fastest thing we act on.

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