Question

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : PH3 has lower boiling point than NH3.
Reason (R) : In liquid state NH3 molecules are associated through vander waal’s forces, but PH3 molecules are associated through hydrogen bonding.
In the light of the above statements.
Choose the most appropriate answer from the options given below:

• A. Both (A) and (R) are correct and (R) is not the correct explanation of (A)
• B. (A) is not correct but (R) is correct
• C. Both (A) and (R) are correct but (R) is the correct explanation of (A)
• D. (A) is correct but (R) is not correct

Answer 1

Answer: (D)

(A) is correct but (R) is not correct

Answer 2

Unlike $\text{NH}_3$, $\text{PH}_3$ molecules are not associated through hydrogen bonding in the liquid state.

This is why the boiling point of $\text{PH}_3$ is lower than that of $\text{NH}_3$.