Calcium bisulfite

Calcium bisulfite (calcium bisulphite) is an inorganic compound which is the salt of a calcium cation and a bisulfite anion. It may be prepared by treating lime with an excess of sulfur dioxide and water. As a food additive it is used as a preservative under the E number E227. Calcium bisulfite is an acid salt and behaves like an acid in aqueous solution. It is used in the sulfite process for producing paper from wood chips.[1]

Calcium bisulfite

Names
IUPAC name Calcium hydrogen sulfite
Other names Calcium bisulphite E227
Identifiers
CAS Number	13780-03-5^Y
3D model (JSmol)	Interactive image
ChemSpider	24475^Y
ECHA InfoCard	100.034.007
E number	E227 (preservatives)
PubChem CID	26268
RTECS number	EV9294500
UNII	SNM7K02JP2^Y
CompTox Dashboard (EPA)	DTXSID50889620
InChI InChI=1S/Ca.2H2O3S/c;2*1-4(2)3/h;2*(H2,1,2,3)/q+2;;/p-2^Y Key: LVGQIQHJMRUCRM-UHFFFAOYSA-L^Y InChI=1/Ca.2H2O3S/c;2*1-4(2)3/h;2*(H2,1,2,3)/q+2;;/p-2 Key: LVGQIQHJMRUCRM-NUQVWONBAX
SMILES OS(=O)[O-].OS(=O)[O-].[Ca+2]
Properties
Chemical formula	Ca(HSO3)2
Molar mass	202.22 g/mol
Melting point	203 °C
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is ^YN ?)
Infobox references

See also

• Pulp (paper)
• Potassium bisulfite
• Sodium bisulfite

References

1. Patt, Rudolf; Kordsachia, Othar; Süttinger, Richard; Ohtani, Yoshito; Hoesch, Jochen F.; Ehrler, Peter; Eichinger, Rudolf; Holik, Herbert; Hamm (2000). "Paper and Pulp". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a18_545.