Same chapter3 marksDifficulty: Medium
Why is sulphur hexafluoride known but not sulphur hexachloride?
p-Block Elements
3 marksDifficulty: Medium
Why is ammonia a stronger base than phosphine?
Original Khojo Papers practice question — not from a past board paper.
Answer
The nitrogen atom is much smaller than phosphorus, so its lone pair is concentrated in a smaller volume and is much more readily donated to a proton. In phosphine the lone pair is spread over a larger atom and is far less available.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The same size effect explains the fall in basicity down the group.
Related questions
From the same topic and chapter, at a similar level.
Same chapter3 marksDifficulty: Medium
Why are the noble gases chemically inert, and which of them forms compounds most readily?
p-Block Elements
Same chapter3 marksDifficulty: Medium
Explain why nitrogen does not form pentahalides while phosphorus does.
p-Block Elements
Same chapter3 marksDifficulty: Medium
Why is the boiling point of hydrogen fluoride higher than that of hydrogen chloride?
p-Block Elements
Same subject3 marksDifficulty: Medium
What is the van't Hoff factor, and what values does it take for sodium chloride and for acetic acid in benzene?
Solutions
Same subject3 marksDifficulty: Medium
Distinguish between Schottky and Frenkel defects and state the effect of each on density.
Solid State