Among the hydrides of Group-15 elements, which have the
lowest boiling point

Explanation

To determine which hydride of Group 15 elements has the lowest boiling point, we will analyze the hydrides of the elements in this group: nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi). The hydrides corresponding to these elements are:

1. NH₃ (Ammonia)
2. PH₃ (Phosphine)
3. AsH₃ (Arsine)
4. SbH₃ (Stibine)
5. BiH₃ (Bismuthine)

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