In fact, many molecular compounds are already completely gaseous at room temperature. In contrast, the ions in ionic compounds are held together by strong attractive forces, so ionic compounds generally have higher melting and boiling points than do molecular compounds." Page 193(215 of 971)
Compound B= Molecular compound(Vaporizes faster and has a lower boiling/melting point)
Compound A= Ionic compound(Vaporizes slower and has a higher boiling/melting point)
