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EC number: 231-668-3 | CAS number: 7681-52-9
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Endpoint summary
Administrative data
Description of key information
Additional information
General remark:
Sodium hypochlorite does not exist as a pure salt at room temperature. It is produced and handled in form of aqueous solutions only. In general, sodium hypochlorite solutions contain between 12 to 16 % (w/w) available chlorine. However concentrations up to 24 % available chlorine can be produced mainly for industrial use. Owing to these facts, this chapter is mainly based on data of recently performed studies on a 24 % available chlorine solution (as this is the highest technically feasible concentration) and on literature data, which also addresses those physical-chemical parameters which are meaningful for sodium hypochlorite.
Summary of physical and chemical properties:
Appearance: |
Yellow, limpid liquid with a chlorinated odour (Tieche, A., 2007) |
Melting point. |
-28.9 +/- 0.5 °C (purity: 24.3 % available chlorine) (Tieche, A., 2007) |
Boiling point: |
As sodium hypochlorite solution is an aqueous mixture of an inorganic salt, water will evaporate when heating the solution. After removal of water, white crystals are observed on the bottom of the test and boiling point cannot be determined (Tieche, A., 2007). |
Relative density: |
D (21.2°C/4 °C) = 1.300 +/-0.001 |
Granulometry |
In accordance with colum 2 of REACH Annex VII, the particle size determination test (required in section 7.14) does not need to be conducted as sodium hypochlorite is marketed or used in a non solid or granular form. |
Vapour pressure: |
negligible |
Henry’s law constant: |
negligible |
Solubility in water: |
Sodium hypochlorite is completely miscible in water. |
Dissociation constant: |
K = 2.9 x 10-8 (at 25 °C); pK = 7.53 (Pinto, G., 2003). |
Partition coefficient: |
The log Pow of NaOCl was calculated to be: log Pow : - 3.42 |
Thermal stability: |
Half life of a 10 % av Cl solution at different temperatures: and for a 5 % solution: 15 °C: 5000 days; 25°C: 790 days Relevant breakdown products are chlorate and chloride (White, G., 1972). |
Auto flammability |
In accordance with column 2 of REACH annex VII, the study does not need to be conducted for liquids non flammable in air. The sodium hypochlorite solution has no flash point up to 111°C, temperature at which the product starts to decompose. Thus the sodium hypochlorite solution is non flammable in air and the auto-flammability test is not required. |
Flammability |
For a liquid such as the aqueous solution of sodium hypochlorite, the primary value for ease of ignition is the flash point. No flash point was observed up to 111°C. Thus the substance is not regarded as flammable. A test on flammability in contact with water does not need to be conducted as the substance is marketed and used in aqueous solution and experience in handling and use gives no indications that the substance reacts with water. A test on pyrophoric properties does not need to be conducted as experience in handling and use gives no indications that the substance ignites or reacts with air. |
Flash point: |
No flash point was observed up to 111°C. No main test was performed. |
Surface tension: |
82.4 mN/m +/-0.8 mN/m at 20.2-20.3°C (Ferron, N., 2007) |
Explosive properties: |
In accordance with column 2 of REACH Annex VII, explosive properties (required in section 7.11) does not need to be conducted as there are no chemical groups associated with explosive properties present in sodium hypochlorite (refer to Guidance on information requirements and chemical safety assessment, Chapter R.7a). |
Oxidising properties: |
The mean pressure rise time obtained with the mixture test item / cellulose was slower than the mean pressure rise time obtained with the mixture reference item / cellulose thus sodium hypochlorite 100 does not have oxidising properties. As testing was triggered by the presence of hypochlorite ions, the lack of oxidising propertie in sodium hypochlorite 100 indicates that solutions with a lower sodium hypochlorite concentration will not have oxidising properties. |
Stability in organic solvents and identity of relevant degradation products |
In accordance with column 2 of REACH Annex IX, Stability in organic solvents and identity of relevant degradation products (required in section 7.15) does not need to be conducted as Sodium hypochlorite is inorganic. |
pH |
The pH value of sodium hypochlorite solutions is alkaline. The pH value of a 5 % sodium hypochlorite solution was determined to be |
Viscosity |
Viscosity:6.2 – 6.6 mPa.s (at 20°C ± 0.2°C) Viscosity:4.0 mPa.s For lower purities of sodium hypochlorite (5 % and 14 %) also lower viscosity values were measured (Tieche, A., 2007). |
Reactivity towards container material: |
Common metals should never be used for the storage and handling of sodium hypochlorite.Suitable materials are: PVDF,PTFEE, PVC, CPVC (NF EN 901, 1999). |
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
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