Same chapter3 marksDifficulty: Medium
Explain why carbon dioxide is non-polar although each C=O bond is polar.
Chemical Bonding and Molecular Structure
3 marksDifficulty: Medium
What is hydrogen bonding? Explain why water has a much higher boiling point than hydrogen sulphide.
Original Khojo Papers practice question — not from a past board paper.
Answer
A hydrogen bond is the attraction between a hydrogen atom bonded to a small, highly electronegative atom and a lone pair on such an atom in another molecule. Water molecules are held together by extensive hydrogen bonding, which needs a great deal of energy to break; hydrogen sulphide, with a much less electronegative sulphur atom, forms no significant hydrogen bonds, so it boils far lower despite its greater molecular mass.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The same effect explains why ice is less dense than water.
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