Hypokloritjoner

Hypokloritjoner, or hypochlorite ions, are the chemical anion OCl−, the conjugate base of hypochlorous acid HOCl. In water, hypochlorite exists in equilibrium with HOCl, and the relative amounts depend on the pH of the solution. HOCl is a stronger oxidizing agent and disinfectant than OCl−; at lower pH, HOCl dominates, while at higher pH the OCl− form is more prevalent.

Hypochlorite is widely used as a disinfectant and bleaching agent. It occurs in oxidized chlorine solutions and is produced industrially as sodium hypochlorite NaOCl in aqueous solution, commonly known as household bleach. Calcium hypochlorite is another commercial source. In water treatment, hypochlorite-based systems inactivate microorganisms through oxidation and chlorination.

Reactivity and stability: As an oxidizing agent, hypochlorite oxidizes a range of organic and inorganic substrates. It can react with ammonia or amines to form chloramines, a pathway used in some disinfection strategies. Under certain conditions hypochlorite decomposes, releasing chloride and oxygen, and it can disproportionate to chlorate at elevated temperatures or concentrations: 3 OCl− → ClO3− + 2 Cl−. Solutions are sensitive to light, heat, metals, and organic matter, which can reduce efficacy and generate byproducts.

Safety and environmental aspects: Hypochlorite solutions are corrosive and strong oxidizers. They can release chlorine gas if acidified, so mixing with acids or ammonia should be avoided. Residual hypochlorite can react with organic matter to form disinfection byproducts; proper handling and storage are important to minimize risks.