What is sodium hypochlorite?
Sodium hypochlorite, also known as bleach or Javel, has the chemical formula NaOCl. It is a liquid solution with strong oxidizing properties, capable of breaking down color pigments in substances and the biological structures of microorganisms. Therefore, NaOCl is widely used as a bleaching and disinfecting agent in industrial, domestic, and medical fields.
Applications in daily life and industry:
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In everyday life: Javel is a common bleaching agent used to whiten or remove stains and yellowing on clothes and fabrics. Specifically, when the Javel solution is dissolved in water, it forms hypochlorous acid (HOCl), a weak acid with strong oxidizing properties, used for bleaching clothes and removing stains. Hypochlorous acid acts on dye molecules in fabrics, breaking bonds and preventing dye molecules from absorbing light, which helps remove dirt and unpleasant odors.
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Water disinfection, especially in swimming pools: Sodium hypochlorite demonstrates antibacterial properties by reacting with bacterial proteins and DNA, disrupting cell membranes, thereby killing and preventing their growth. This ensures that pool water remains clean and safe.
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Industrial wastewater treatment: Sodium hypochlorite is widely used in industrial wastewater treatment to remove and prevent the spread of bacteria and sludge, particularly in treating diluted or concentrated cyanide in wastewater. NaOCl creates oxidation reactions that convert toxic cyanide into cyanate (OCN⁻): CN⁻ + OCl⁻ → OCN⁻ + Cl⁻.
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Medical field: Sodium hypochlorite is extensively used as a disinfectant. Depending on the application, it can be diluted to appropriate concentrations. It is used in dental procedures to eliminate bacteria in tooth pulp, with concentrations ranging from 0.5% to 5.25%. Additionally, NaOCl is used to prevent and treat skin and tissue infections, especially before and after surgeries to prevent infection.
