Question

Assertion : Hydrides of N, O and F have lower boiling points than the hydrides of their subsequent group members.
Reason : Boiling point depends upon the molecular mass only.
A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer 1

Correct Answer - D
Boiling point depends upon intermolecular forces. Due to higher electronegativity of N, O and F, the magnitude of hydrogen bonding in their hydrides will be quite high. Hence their biling points will be higher than the hydrides of their subsequent group members.