Same chapter3 marksDifficulty: Medium
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3 marksDifficulty: Medium
Arrange Na+, Mg2+, F− and O2− in order of increasing ionic radius and give the reason.
Original Khojo Papers practice question — not from a past board paper.
Answer
Mg2+ < Na+ < F− < O2−. All four are isoelectronic with 10 electrons, so the radius falls as the nuclear charge rises: O2− has 8 protons, F− 9, Na+ 11 and Mg2+ 12.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
For isoelectronic species the greater the nuclear charge, the smaller the ion.
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