NaCl

Sodium chloride (NaCl) is an ionic compound composed of sodium ions (Na+) and chloride ions (Cl−) in a 1:1 ratio. In the solid state it forms a cubic crystal lattice and has a high melting point. It dissolves readily in water, producing a neutral solution of Na+ and Cl−. In nature it occurs as the mineral halite and is the dominant component of seawater salts and rock salt.

NaCl occurs widely in nature, notably in seawater and evaporite deposits. It exists as the mineral halite and is obtained commercially from underground rock salt deposits or by evaporating seawater in large ponds to crystallize the salt.

Commercial production combines mining or quarrying of rock salt with processing, and, for large-scale chemical production, brine electrolysis. The electrolysis of brine yields chlorine gas, sodium hydroxide, and hydrogen as byproducts, making NaCl a key feedstock for the chlor-alkali industry.

Major uses include food seasoning and preservation. Industrially, NaCl supplies chlorine and sodium hydroxide, which are essential chemicals in manufacturing, plastics, paper, and water treatment. It is also used for de-icing roads, in water softening, and in various agricultural and pharmaceutical applications.

Biologically, sodium chloride is essential for humans and other animals, contributing to extracellular fluid balance, nerve function, and muscle activity in appropriate amounts. Excessive intake can be linked to health concerns such as hypertension.

Safety and handling: food-grade salt is widely regarded as safe, but high intake has health risks. Inhalation of salt dust can irritate the respiratory tract, and chloride ions in moist environments can promote corrosion of metals; store and handle accordingly in a dry, labeled container.