Question

What is the trend of boiling points of hydrides of N, O and F?

• A. Due to lower molecular masses $NH_{3},H_{2}O$and HF have lower boiling points than those of the subsequent group member hydrides.
• B. Due to higher electronegativity of N, O and F; $NH_{3},H_{2}O$and HF show hydrogen bonding and hence higher boiling points than the hydrides of their subsequent group members.
• C. There is no regular trend in the boiling points of hydrides.
• D. Due to higher oxidation states of N, O and F, the boiling points of $NH_{3},H_{2}O$and HF are higher than the hydrides of their subsequent group members.

Answer 1

Answer: (B)

Due to higher electronegativity of N, O and F; $NH_{3},H_{2}O$and HF show hydrogen bonding and hence higher boiling points than the hydrides of their subsequent group members.

Answer 2

: Due to higher electronegativity the extent of hydrogen bonding is quite appreciable.