Ferric oxalate

Ferric oxalate

Names
Systematic IUPAC name iron(3+) ethanedioate (2:3)
Other names Iron(III) oxalate
Identifiers
CAS Number	2944-66-3 (Anhydrous) 166897-40-1 (hexahydrate)
ChemSpider	147789
EC Number	220-951-7
Jmol interactive 3D	Image
PubChem	168963
InChI InChI=1S/3C2H2O4.2Fe/c3*3-1(4)2(5)6;;/h3*(H,3,4)(H,5,6);;/q;;;2*+3/p-6
SMILES [Fe+3].[Fe+3].O=C([O-])C([O-])=O.[O-]C(=O)C([O-])=O.[O-]C(=O)C([O-])=O
Properties
Chemical formula	C6Fe2O12
Molar mass	375.747 g/mol
Appearance	Pale yellow solid (anhydrous) Lime green solid (hexahydrate)
Odor	odorless
Solubility in water	slightly soluble
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Ferric oxalate, also known as iron(III) oxalate, is a chemical compound composed of ferric ions and oxalate ligands; it may also be regarded as the ferric salt of oxalic acid. The anhydrous material is pale yellow; however, it may be hydrated to form Fe₂(C₂O₄)₃·6H₂O which is bright green in colour

Like many oxalates, ferric oxalate has been investigated as a short term treatment for dentin hypersensitivity.^[1] It is used in certain toothpaste formulations; however, its effectiveness has been questioned.^[2]

It is used as the light-sensitive element in the Kallitype photographic printing process.

See also

A number of other iron oxalates are known:-

• Iron(II) oxalate
• Potassium ferrioxalate
• Sodium ferrioxalate

References

1. Gillam, D. G.; Newman, H. N.; Davies, E. H.; Bulman, J. S.; Troullos, E. S.; Curro, F. A. "Clinical evaluation of ferric oxalate in relieving dentine hypersensitivity". Journal of Oral Rehabilitation 31 (3): 245–250. doi:10.1046/j.0305-182X.2003.01230.x.
2. Cunha-Cruz, J.; Stout, J. R.; Heaton, L. J.; Wataha, J. C. (29 December 2010). "Dentin Hypersensitivity and Oxalates: a Systematic Review". Journal of Dental Research 90 (3): 304–310. doi:10.1177/0022034510389179.