If the melting and boiling points are both below room temp, you have a solid. If they’re both above room temp, the compound is a gas. If the boiling point is above room temp and the melting point is below, the compound is a liquid. States are represented by (s) for solid, (l) for liquid, (g) for gas, or (aq) for aqueous solution. The amount of energy in molecules of matter determines the state of matter.