Same chapter3 marksDifficulty: Medium
Arrange Na+, Mg2+, F− and O2− in order of increasing ionic radius and give the reason.
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3 marksDifficulty: Medium
Why does the atomic radius of the noble gases appear larger than that of the halogen before them?
Original Khojo Papers practice question — not from a past board paper.
Answer
The radius of a noble gas is measured as a van der Waals radius, half the distance between two non-bonded atoms, because noble gases form almost no bonds. The halogen radius is a covalent radius, half the distance between two bonded atoms, which is necessarily smaller. The two are not comparable measures.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
This is why the trend appears to break at the end of each period.
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