Magnesium sulfite

Names

IUPAC name

Magnesium sulfite

Other names

Magnesium sulphite

Identifiers

CAS Number

7757-88-2^Y

ChemSpider

2282946

ECHA InfoCard

100.028.932

EC Number

231-825-6

PubChem CID

3014583

UNII

792J6K230W^Y

CompTox Dashboard (EPA)

DTXSID50884418

Properties

Chemical formula

MgSO
₃ (anhydrous); MgSO
₃·6H
₂O

Molar mass

104.368200 g/mol (anhydrous)
212.4599 g/mol (hexahydrate)

Solubility in water

5.2g/L at 298.2K (hexahydrate)

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Infobox references

Chemical compound

Magnesium sulfite is the magnesium salt of sulfurous acid with the formula MgSO
₃. Its most common hydrated form has 6 water molecules making it a hexahydrate, MgSO
₃·6H
₂O. When heated above 40 °C (104 °F), it is dehydrated to magnesium sulfite trihydrate, or MgSO
₃·3H
₂O.^[1] The anhydrous form is hygroscopic, meaning that it readily absorbs water from the air.

Solubility tables of MgSO3 hydrates PDF: ^[2]

References

^ Nývlt, J., "Solubilities of Magnesium Sulfite," Journal of Thermal Analysis and Calorimetry, Volume 66, Number 2 / November, 2001
^ [1], H.D.Lutz, Dept. of Chemistry, University of Slegen.