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Diss Factsheets
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EC number: 432-070-7 | CAS number: -
- 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
Dissociation constant
Administrative data
Link to relevant study record(s)
Description of key information
The pKA was determined as 7.00 ± 0.04.
Key value for chemical safety assessment
- pKa at 20°C:
- 7
Additional information
The test item reacts like a base with one proton acceptor unit, corresponding to a pKA= 7.00 of the conjugated acid. As the test item consists of several components, it was expected to find several turning points for each of the proton acceptor units which are present in the mixture. However, in all four titrations, only one point of equivalence could be detected. Therefore, it is believed, that the pKAwhich could be detected is the pKAof the reaction of the hydroxysulfinatoacetate dianion with H+ to the mono- anion overlapped by the corresponding pKAof the hydroxysulfonatoacetate dianion. The second pKA-sof both hydroxysulfinatoacetate acid and hydroxysulfonatoacetate acid are too low for a determination in aqueous systems.
The pKA-s of sodium sulphite are stated in the literature. The first pKAlies outside the determination limit in aqueous systems. The second pKAis probably overlapping with the turning point of the hydroxysulfinatoacetate respectively hydroxysulfonatoacetate dianion. It is believed that the pKA7.00 is correlated to a mixture of dissociations.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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