Ion–dipole intermolecular forces occur between ions and polar molecules. Dipole–dipole intermolecular forces occur between polar molecules. Hydrogen bonds are intermolecular forces between dipoles in which there is a hydrogen
atom attached to an N, O, or F atom.
Ion-induced dipole intermolecular forces occur between an ion and a nonpolar molecule. London (dispersion) forces are intermolecular forces between nonpolar molecules. Liquids possess surface tension (liquids behaving as if they had a thin “skin” on their
surface, due to unequal attraction of molecules at the surface of the liquid), viscosity
(resistance to flow), and capillary action (flow up a small tube).
Amorphous solids have very little structure in the solid state. Crystalline solids have a great deal of structure in the solid state. The crystal lattice of a crystalline solid is the regular ordering of the unit cells. Cubic unit cells include the simple body-centered, and face-centered. Know the five types of crystalline solid: atomic, molecular, ionic, metallic, and network. A phase diagram is a graph displaying the relationship of a substance’s states of matter to
temperature and pressure.
The critical point on a phase diagram is that point beyond which the gaseous and liquid
states merge. No matter how much pressure is applied or how much the gas is cooled, the
substance cannot be condensed into a liquid.
The triple point is the combination of temperature and pressure on a phase diagram
where all three states of matter exist in equilibrium.
Phase changes can be related to the strength of intermolecular forces.178 Step 4. Review the Knowledge You Need to Score High