Polarity and Intermolecular Forces

Have you ever seen a water strider skimming across the surface of a pond? The water strider takes advantage of a property called surface tension. This allows the bug to “walk” on the water as if it were on solid ground.

Water has surface tension because water molecules are polar and strongly attracted to one another. Polarity and the resulting forces are explored in the Polarity and Intermolecular Forces Gizmo. In the Gizmo, students start by classifying bonds between atoms as ionic, polar covalent, or nonpolar covalent. Students then measure the polarity of molecules and three types of intermolecular forces: dipole-dipole, dipole-induced dipole, and London dispersion forces.

After learning about molecular polarity, students can explore the resulting properties of liquids, including surface tension, using the Sticky Molecules Gizmo.