The elements of group 5A,the nitrogen family,form compounds with hydrogen having the boiling points listed below: SbH₃,-17 °C; AsH₃,-55 °C; PH₃,-87 °C; and NH₃,-33 °C
The first three compounds illustrate a trend where the boiling point decreases as the mass decreases; however,ammonia (NH₃) does not follow the trend because of _____.

Question

Quizplus · Accepted Answer

Ammonia (NH₃) is able to form hydrogen bonds between the nitrogen and hydrogen atoms, which are stronger than the London dispersion forces present in the other compounds. This results in a higher boiling point for ammonia, even though it has a lower mass than the other compounds in the trend.

The Elements of Group 5A,the Nitrogen Family,form Compounds with Hydrogen