Disodium selenite pentahydrate
A hydrate that is the pentahydrate form of disodium selenite. — ChEBI
Safety documents & references
1 indexed referencesFind a product-specific SDS
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Identity & molecular properties
Source-linked values| CAS number | 26970-82-1 | ChEBI ↗ |
| Molecular formula | 5H2O.2Na.O3Se | ChEBI ↗ |
| Molar mass | 263.012 g/mol | ChEBI ↗ |
| Monoisotopic mass | 263.93363 Da | ChEBI ↗ |
| Formal charge | 0 | ChEBI ↗ |
| ChEBI identifier | CHEBI:131361 | ChEBI ↗ |
Cross-source molecular data
PubChem| Molar mass | 263.03 g/mol | PubChem ↗ |
| Exact mass | 263.93363 Da | PubChem ↗ |
PubChem computed values are shown separately from the ChEBI record. An exact InChIKey match was used to connect the records. Molecular descriptors do not describe a supplied product’s purity, particle size or performance.
Names & structural identifiers
Copy any identifierdisodium selenite pentahydratesodium selenite--water (1/5)TUANAMBRHOLYTH-UHFFFAOYSA-LO.O.O.O.O.O=[Se]([O-])[O-].[Na+].[Na+]InChI=1S/2Na.H2O3Se.5H2O/c;;1-4(2)3;;;;;/h;;(H2,1,2,3);5*1H2/q2*+1;;;;;;/p-2Names & synonyms
Names are supplied by ChEBI. Trade names and related synonyms may describe a broader product context.
Classification & relationships
ChEBI ontologyRoles recorded in ChEBI
Database role annotations describe reported biological or chemical roles; they are not product approvals or recommendations for use.
Safety classification · Japan
NITE / Japanese governmentSelenious acid, (H2SeO3), disodium salt, pentahydrate · 1064
| Endpoint | Reported classification |
|---|---|
| Serious eye damage/eye irritation | Category 2A-2B |
| Specific target organ toxicity - Single exposure | Category 3 （Respiratory tract irritation） |
| Hazardous to the aquatic environment （Acute） | Category 1 |
| Hazardous to the aquatic environment （Long-term） | Category 1 |
Selected source-reported endpoints. Other endpoints, rationales and conditions remain in the original classification. Missing or unlisted information does not mean non-hazardous. This is not a global classification or transport decision.
Read the original NITE classificationMass ↔ amount of substance
Calculated from sourced massUses 263.012 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.
Research & patent references
Selected source associationsSources & record history
Checked 27 Sep 2026Release 255, 9 September 2026. ChEBI three-star (manually annotated) source entry. View original record ↗ · CC BY 4.0
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