Sodium chloride

Sodium chloride /ˌsoʊdiəm ˈklɔːraɪd/, also known as salt or halite, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. Sodium chloride is the salt most responsible for the salinity of seawater and of the extracellular fluid of many multicellular organisms. In the form of edible or table salt it is commonly used as a condiment and food preservative. Large quantities of sodium chloride are used in many industrial processes, and it is a major source of sodium and chlorine compounds used as feedstocks for further chemical syntheses. A second major consumer of sodium chloride is de-icing of roadways in sub-freezing weather.

Chemistry

Solid sodium chloride

In solid sodium chloride, each ion is surrounded by six ions of the opposite charge as expected on electrostatic grounds. The surrounding ions are located at the vertices of a regular octahedron. In the language of close-packing, the larger chloride ions are arranged in a cubic array whereas the smaller sodium ions fill all the cubic gaps (octahedral voids) between them. This same basic structure is found in many other compounds and is commonly known as the halite or rock-salt crystal structure. It can be represented as a face-centered cubic (fcc) lattice with a two-atom basis or as two interpenetrating face centered cubic lattices. The first atom is located at each lattice point, and the second atom is located half way between lattice points along the fcc unit cell edge.

Sodium chloride (data page)

This page provides supplementary chemical data on sodium chloride.

Material safety data sheet

The handling of this chemical may incur notable safety precautions. It is highly recommended that you seek the material safety data sheet (MSDS) for this chemical from a reliable source such as MSDS Search Engine, and follow its direction.

Structure and properties

Thermodynamic properties

Spectral data

References

Except where noted otherwise, data relate to standard ambient temperature and pressure.

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