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Green to yellow watery liquid with an odor of bleaching liquid odor. Sinks and mixes with water.

Salts of hypochlorous acid, HClO. Generally toxic, irritants and powerful oxidizers, particularly in the presence of water at higher temperature as they decompose to release oxygen and chlorine gases. On contact with urea they form the highly explosive NCl3 . When heated or on contact with acids, they produce highly toxic fumes of chlorine gas [Sax, 9th ed., 1996, p. 1905]. Can react with sulfuric acid to produce heat and chlorine gas.

Water soluble. Decomposes into chlorine and oxygen gases in hot water.

Fire risk in contact with organic materials. Toxic by ingestion, strong irritant to tissue.

Liquid can be irritating to skin and eyes if contact is maintained.

Behavior in Fire: May decompose, generating irritating chlorine gas.

Anhydrous sodium hypochlorite explodes; the pentahydrate is a pale-green crystalline solid; orthorhombic structure; density 1.6 g/cm³; melts at 18°C; decomposed by CO2 in the air; soluble in water, 29.3 g/100 mL at 0°C; the aqueous solution is highly stable.

Sodium hypochlorite exists as an aqueous solution from 5 15% NaOCl and is commonly called bleach. Household bleach is typically a 5.25% solution, and industrial bleach is sold as a 12% solution. When sodium hypochlorite is used in this entry, it is assumed to be the aqueous solution, which is clear, slightly yellow, corrosive, and has a distinctive chlorine smell. Chorine gas was discovered by Carl Wilhelm Scheele (1742 1786) in 1774 and known initially as depholgisticated salt spirit. In 1787, the French chemist Claude Louis Berthollet (1749 1822) experimented with aqueous solution of chlorine gas as bleaching agents. Based on Berthollet's work, the Javel Company located on the outskirts of Paris began to produce bleaches in 1788. Chlorine gas was dissolved in a solution of soda potash (potassium carbonate) to obtain a product called liqueur de Javel, which was potassium hypochlorite. Potash treated with chlorine gas was also used to produce bleaching powders. In 1820, Antoine Germaine Labarraque (1777 1850), an apothecary, substituted cheaper soda ash (sodium carbonate) for potash to produce Eau de Labarraque or Labarraque solution, which was sodium hypochlorite. Eau de Labarraque was used as a disinfectant and to bleach paper. Bleaching powders, borax, lye, and blueing were used as bleaches throughout the 19th century.
Sodium hypochlorite is the primary hypochlorite used as a bleach and disinfectant, accounting for 83% of world hypochlorite use, with calcium hypochlorite accounting for the remaining 17%. Approximately 1 million tons of sodium hypochlorite was used globally in 2005, with about half this amount used in households for laundry bleaching and disinfection. The other half was used primarily for wastewater and drinking water treatment; other uses include pool sanitation, bleaching of pulp, paper, and textiles, and as an industrial chemical.

ChEBI: An inorganic sodium salt in which hypochlorite is the counterion.

Nonflammable

Sodium hypochlorite, commonly known as bleach, may be used as a disinfectant solution. It is a strong irritant; however, isolated reports of CoU to sodium hypochlorite exist. The mechanism for the Cou is uncertain.
Hostynek et al. describe a 36-year-old woman who developed an intensely pruritic maculopapular rash to a hypochlorite-containing cleaning product that she spilled on her leg. The rash progressed to involve her trunk and extremities and was associated with teary eyes, dyspnea, and facial edema. There was a history of a previous sensitizing event, and open testing to 1% sodium hypochlorite produced an immediate urticarial reaction. The authors suggest that this could be due to an immunological mechanism given the generalized symptoms; however, no confirmatory testing was performed and the potential of sodium hypochlorite to cause nonimmunologic Cou was evident with four of 10 controls experiencing a wheal-and-flare reaction to open application of 6% sodium hypochlorite.
Caliskan et al. described a 32-year-old female who developed severe lip edema and breathing difficulty after using a sodium hypochlorite irrigation during endodontic treatment. A scratch test to sodium hypochlorite resulted in immediate erythema and edema that began to extend up the patient’s arm. She also had a history of breathing difficulties and had developed dermatitis from her hands to elbows with the use of household cleaning agents.
Neering reported on a patient who had experienced intermittent Cou to chlorinated pools and contact with a cleansing agent containing sodium hypochlorite. A scratch test to chlorinated water was strongly positive in this patient, but negative in five controls, and closed patch testing to sodium hypochlorite was strongly positive at three hours.