Same chapter3 marksDifficulty: Medium
Why is sulphur hexafluoride known but not sulphur hexachloride?
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3 marksDifficulty: Medium
Explain why nitrogen does not form pentahalides while phosphorus does.
Original Khojo Papers practice question — not from a past board paper.
Answer
Nitrogen is in the second period and has no d orbitals available, so it cannot expand its octet beyond four bonds. Phosphorus is in the third period, has vacant 3d orbitals and can therefore accommodate five bonding pairs, forming PCl5.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The same reason explains why nitrogen has a maximum covalency of four.
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