Sodium selenite

Sodium selenite is a chemical compound. Its chemical formula is Na₂SeO₃. It contains sodium and selenite ions.

Sodium selenite

Identifiers
CAS Number	10102-18-8 (hydrate: 26970-82-1) N
3D model (JSmol)	Interactive image
ChEBI	CHEBI:48843 Y
ChEMBL	ChEMBL112302 Y
ChemSpider	23308 Y
ECHA InfoCard	100.030.230
EC Number	233-267-9
KEGG	D10530 N
PubChem CID	24934
RTECS number	VS7350000
UNII	HIW548RQ3W Y
UN number	2630
CompTox Dashboard (EPA)	DTXSID0032077
SMILES [Na+].[Na+].[O-][Se]([O-])=O
Properties
Chemical formula	Na2O3Se
Molar mass	172.95 g·mol−1
Appearance	colorless solid
Density	3.1 g/cm3
Melting point	decomposes at 710 °C
Solubility in water	85 g/100 mL (20 °C)
Solubility	insoluble in alcohol, ethanol
Structure
Crystal structure	tetragonal
Pharmacology
ATC code	A12CE02 (WHO)
Hazards
EU classification	Very toxic (T+) Dangerous for the environment (N)
NFPA 704	0 3 0
R-phrases	R23, R28, R31, R43, R51/53
S-phrases	(S1/2), S28, S36/37, S45, S61
Related compounds
Related compounds	{{{value}}}
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YN ?)
Infobox references

Properties

Sodium selenite is a white solid. It dissolves in water. It is a weak oxidizing agent. It reacts with acids to make selenous acid. It can be oxidized by powerful oxidizing agents to make sodium selenate.

Preparation

It is made by reacting sodium hydroxide with selenium dioxide

2 NaOH + SeO₂ → Na₂SeO₃ + H₂O

Uses

Sodium selenite is used to add a pink color to glass. It is also used in some vitamin supplements.

Safety

Eating of any more than a very tiny amount would give selenium poisoning.

Related pages

• Sodium selenide