Contents

Chromium(II) oxalate

Chromium(II) oxalate

Names
IUPAC name Chromium(2+) oxalate
Identifiers
CAS Number	814-90-4 Y
3D model (JSmol)	Interactive image
ChemSpider	12595
ECHA InfoCard	100.011.282
PubChem CID	13147
UNII	RV83VA978Q Y
CompTox Dashboard (EPA)	DTXSID90231083
InChI InChI=1S/C2H2O4.Cr/c3-1(4)2(5)6;/h(H,3,4)(H,5,6);/q;+2/p-2 Key: XVHFYNOGAFYRJV-UHFFFAOYSA-L InChI=1/C2H2O4.Cr/c3-1(4)2(5)6;/h(H,3,4)(H,5,6);/q;+2/p-2 Key: XVHFYNOGAFYRJV-NUQVWONBAE
SMILES C(=O)(C(=O)[O-])[O-].[Cr+2]
Properties
Chemical formula	Cr(C2O4)
Molar mass	140.02 g/mol
Appearance	light green crystals
Density	2.461 g/cm3
Solubility in water	126 g/100 mL (0 °C)
Solubility	negligible in alcohol
Related compounds
Other cations	Iron(II) oxalate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Chemical compound

Chromium(II) oxalate is an inorganic compound with the chemical formula CrC₂O₄.

Preparation[edit]

According to Nikumbh et al., CrC₂O₄·2H₂O can be prepared from chromium(II) sulfate pentahydrate by reaction with a mixture of sodium oxalate and oxalic acid in degassed aqueous solution, forming a light green crystalline product, which has been characterized by combustion elemental analysis, infrared spectroscopy, thermogravimetric analysis and powder X-ray diffraction.^[1] The measured magnetic moment of 4.65 B.M. suggests that the chromium ion does not form a Cr-Cr bond and has a high-spin octahedral coordination geometry. This would be consistent with the structure of other linear polymeric metal(II) oxalates of general formula MC₂O₄·2H₂O (M = Mg, Fe, etc.).^[2] The dihydrate loses water to form anhydrous CrC₂O₄ when heated above 140 °C in an inert atmosphere. Heating above 320 °C produces a mixture of chromium oxides.^[1]

Milburn and Taube have presented data indicating that chromium(II) will reduce oxalate to glycolate within a few minutes in acidic aqueous solutions, casting some doubt on the formulation of chromium(II) oxalate as a stable Cr²⁺ species if prepared from acidic aqueous solutions.^[3]

References[edit]

This inorganic compound–related article is a stub. You can help Wikipedia by expanding it.