Sodium selenite

chemical compound

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

Sodium selenite
Identifiers
  • 10102-18-8 (hydrate: 26970-82-1) ☒N
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.030.230
EC Number
  • 233-267-9
KEGG
RTECS number
  • VS7350000
UNII
UN number 2630
  • [Na+].[Na+].[O-][Se]([O-])=O
Properties
Na2O3Se
Molar mass 172.95 g·mol−1
Appearance colorless solid
Density 3.1 g/cm3
Melting point decomposes at 710 °C
85 g/100 mL (20 °C)
Solubility insoluble in alcohol, ethanol
Structure
tetragonal
Pharmacology
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
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Properties change

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 change

It is made by reacting sodium hydroxide with selenium dioxide

2 NaOH + SeO2 → Na2SeO3 + H2O

Uses change

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

Safety change

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

Related pages change