Common table salt is odorless, white and cubic in structure. It is hygroscopic, has a melting point of 1,472 degrees Fahrenheit, a boiling point of 2,669 degrees Fahrenheit and a density of 2.165 grams per cubic centimeter. Salt is used as a food additive, an industrial additive and a de-icing agent.
Salt is an ionic compound consisting of sodium and chloride in a face-centered-cubic lattice structure. Salt contains equal portions of chlorine and sodium. Bulk salt crystals are translucent and cubic in shape. Pure salt is white, although impurities may give it a blue or purple tinge.
Salt has a high water solubility of 359 grams per liter. Salt in water solutions can be made to recrystallize as dehydrate sodium chloride, where each sodium chloride molecule is weakly bonded to two water molecules. Adding salt to water changes its physical properties. A salt and water solution has a lower freezing point than just water. As the amount of salt added increases, the freezing point correspondingly decreases until the solubility limit.
Salt used for culinary applications is usually refined to between 97 and 99 percent purity. Additives to table salt include anticaking agents, such as sodium aluminosilicate or magnesium carbonate, which make the salt flow more freely.