Same chapter3 marksDifficulty: Medium
What is hydrogen bonding? Explain why water has a much higher boiling point than hydrogen sulphide.
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3 marksDifficulty: Medium
What is meant by resonance? Illustrate with the carbonate ion.
Original Khojo Papers practice question — not from a past board paper.
Answer
Resonance is the description of a molecule whose real structure cannot be represented by a single Lewis structure, as a hybrid of two or more contributing structures. In the carbonate ion the negative charge and the double bond are shared equally over all three oxygen atoms, so all three C–O bonds are identical and intermediate between a single and a double bond.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The resonance hybrid is more stable than any single contributing structure.
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