Registration Dossier
Registration Dossier
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EC number: 231-673-0 | CAS number: 7681-57-4
Endpoint summary
Administrative data
Description of key information
The majority of data on physico- chemical properties of disodium disulfite were taken from handbooks (including CRC Handbook of Chemistry and Physics and the Merck Index).
Study reports conducted in accordance with EU guidelines are available for: density, solubility in organic solvents, surface tension, auto flammability, flammability and explosive properties.
Waivers are proposed for boiling point, vapour pressure, partition coefficient, flash point, oxidising properties, stability in organic solvents, dissociation constant and viscosity, as well as for auto flammability, pyrophoric properties and flammability in contact with water.
Disodium disulfite (Na2O5S2, molecular weight 190.11 g/mol),CAS No. 7681-57-4, EC No. 231 -673 -0
Disodium disulfite appears as a white crystalline material or as a powder with SO2 odour.
Decomposition temperature: > 150 °C (reliable handbook data)
Relative density: 2.4 (experimental data)
Particle size distribution and dustiness of a representative sample (experimental study results):
D50= 66.8 µm
D10= 9.4 µm
D90= 238.5 µm
Dustiness: 18.55 mg/g, MMAD (GSD): 23.11 µm (2.15).
Water solubility: 667 g/L at 25 °C (very soluble, reliable handbook data)
Solubility in organic solvents: <0.01 g/L for five tested solvents (toluene, dichloromethane, n-hexane, acetone, ethyl acetate); for the methanol, a solubility plateau is reached at 62 g/L after overnight shaking. (experimental data)
Surface tension at 20 °C:
100 mg/L = 55.9 nM/m
500 mg/L = 49.5 nM/m
1000 mg/L = 48.0 nM/m
Flammability: non flammable solid (guideline study; according to EC A.10. – Flammable solids)
Explosiveness: disodium disulfite has no explosive properties (guideline study; according to EC A.14.)
Additional information
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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