The hydrides of group 5A are NH$_3$, PH$_3$, AsH$_3$, and SbH$_3$. Arrange them from highest to lowest boiling point.
Rank the molecules from highest to lowest boiling point. To rank items as equivalent, overlap them.
Highest
NH$_3$ PH$_3$ AsH$_3$ SbH$_3$