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Sodium chloride (NaCl), chemical formula, colorless cubic crystal or fine-grained powder, with salty taste. The appearance is white crystal, and its source is mainly seawater, which is the main component of salt. Soluble in water and glycerol, slightly soluble in ethanol (alcohol) and liquid ammonia; Insoluble in concentrated hydrochloric acid. Impure sodium chloride deliquesces easily in the air. [1] has good stability and its aqueous solution is neutral. Electrolysis of saturated sodium chloride solution is generally used in industry to produce chemical products such as hydrogen, chlorine and caustic soda (commonly known as chlor-alkali industry). It can also be used for ore smelting (electrolysis of molten sodium chloride crystals to produce active metal sodium), preparation of physiological saline in medical treatment and seasoning in life.