Given below are two statements: one is labeled as Assertion (A) and the other is labeled as Reason (R).
Assertion (A): PH3 has lower boiling point than NH3.
Reason (R): In liquid state NH3 molecules are associated through van der Waals' forces, but PH3 molecules are associated through hydr

Question

Given below are two statements: one is labeled as Assertion (A) and the other is labeled as Reason (R).
Assertion (A): PH3 has lower boiling point than NH3.
Reason (R): In liquid state NH3 molecules are associated through van der Waals' forces, but PH3 molecules are associated through hydrogen bonding.
In the light of above statements, choose the most appropriate answer from the options given below.
(1) Both (A) and (R) are correct and (R) is the correct explanation of (A).
(2) Both (A) and (R) are correct but (R) is not the correct explanation of (A).
(3) (A) is correct but (R) is not correct.
(4) (A) is not correct but (R) is correct.

Accepted Answer

(A) is correct but (R) is not correct.. PH3 has a lower boiling point than NH3 due to weaker van der Waals forces in PH3 compared to the strong hydrogen bonding in NH3, making the assertion true. However, the reason provided incorrectly states that PH3 is associated through hydrogen bonding, which is not the case, thus making the reason incorrect.

Solution

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