7.
The elements of Group 5A, the nitrogen family, form compounds with hydrogen that have the boiling points listed below. SbH3 -17°C, AsH3 -55°C, PH3 -87°C, NH3 -33°C
The first three elements illustrate a trend where the boiling point increases as the mass increases; however, ammonia (NH3) does not follow the trend because of
(A) ionic bonding.
(B) hydrogen bonding.
(C) metallic bonding.
(D) dipole-dipole attraction.
(E) London dispersion forces.