By analyzing the relationship between number of electrons in
the molecule and heat of vaporization, students can establish a
relationship between electron count and attractions between
molecules. Students can expand on this by using their
knowledge of electronegativities, molecular geometries, and
molecular polarity developed previously using the Data First
approach to explore the differences in polarity between
molecules and predict how this might affect intermolecular
forces, thus developing a dipole interaction model. They can
sketch their predicted graphs for Groups IV through VII
hydrides based on their developed dipole interaction model and
then compare their predictions to actual supplied data, as in
Figure 4.