Knowledge Base Wiki

Search for LIMS content across all our Wiki Knowledge Bases.

Type a search term to find related articles by LIMS subject matter experts gathered from the most trusted and dynamic collaboration tools in the laboratory informatics industry.

Iron(II) oxalate
Names
IUPAC name
Iron(II) oxalate
Other names
Iron oxalate
Ferrous oxalate
Identifiers
3D model (JSmol)
ECHA InfoCard 100.007.472 Edit this at Wikidata
EC Number
  • 208-217-4
UNII
  • InChI=1S/3C2H2O4.2Fe/c3*3-1(4)2(5)6;;/h3*(H,3,4)(H,5,6);;/q;;;2*+3/p-6 ☒N
    Key: VEPSWGHMGZQCIN-UHFFFAOYSA-H ☒N
  • [Fe+2].O=C([O-])-C([O-])=O
Properties
FeC2O4 (anhydrous)
FeC2O4 · 2 H2O (dihydrate)
Molar mass 143.86 g/mol (anhydrous)
179.89 g/mol (dihydrate)
Appearance yellow powder
Odor odorless
Density 2.28 g/cm3
Melting point dihydrate: 150–160 °C (302–320 °F; 423–433 K)
(decomposes)
dihydrate:
0.097 g/100ml (25 °C)[1]
Hazards
GHS labelling:
GHS07: Exclamation mark[2]
Warning
H302, H312[2]
P280[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Ferrous oxalate (iron(II) oxalate) are inorganic compound with the formula FeC2O4(H2O)x where x is 0 or 2. These are orange compounds, poorly soluble in water.

Structure and reactions

Like other iron oxalates, ferrous oxalates feature octahedral Fe centers. The dihydrate FeC2O4(H2O)x is a coordination polymer, consisting of chains of oxalate-bridged ferrous centers, each with two aquo ligands.[3]
Ball-and-stick model of a chain in the crystal structure of iron(II) oxalate dihydrate

When heated to 120 °C, the dihydrate dehydrates, and the anhydrous ferrous oxalate decomposes near 190 °C.[4] The products of thermal decomposition is a mixture of iron oxides and pyrophoric iron metal, as well as released carbon dioxide, carbon monoxide, and water.[5]

Ferrous oxalates are precursors to iron phosphates, which are of value in batteries.[6]

Natural occurrence

Anhydrous iron(II) oxalate is unknown among minerals as of 2020. However, the dihydrate is known as humboldtine.[7][8] A related, though much more complex mineral is stepanovite,
Na[Mg(H2O)6] [Fe3+(C2O4)3]·3H2O - an example of trioxalatoferrate(III).[9][8]

See also

References

  1. ^ "Iron(II) oxalate dihydrate".
  2. ^ a b c Sigma-Aldrich Co., Iron(II) oxalate dihydrate. Retrieved on 2014-05-03.
  3. ^ Echigo, Takuya; Kimata, Mitsuyoshi (2008). "Single-crystal X-ray diffraction and spectroscopic studies on humboldtine and lindbergite: weak Jahn–Teller effect of Fe2+ ion". Physics and Chemistry of Minerals. 35 (8): 467–475. Bibcode:2008PCM....35..467E. doi:10.1007/s00269-008-0241-7. S2CID 98739882.
  4. ^ Mu, Jacob; Perlmutter, D.D. (1981). "Thermal decomposition of carbonates, carboxylates, oxalates, acetates, formates, and hydroxides". Thermochimica Acta. 49 (2–3): 207–218. doi:10.1016/0040-6031(81)80175-x.
  5. ^ Hermanek, Martin; Zboril, Radek; Mashlan, Miroslav; Machala, Libor; Schneeweiss, Oldrich (2006). "Thermal Behaviour of Iron(II) Oxalate Dihydrate in the Atmosphere of Its Conversion Gases". J. Mater. Chem. 16 (13): 1273–1280. doi:10.1039/b514565a.
  6. ^ Ellis, B. L.; Makahnouk, W. R. M.; Makimura, Y.; Toghill, K.; Nazar, L. F. (2007). "A multifunctional 3.5 V iron-based phosphate cathode for rechargeable batteries". Nature Materials. 6 (10): 749–753. Bibcode:2007NatMa...6..749E. doi:10.1038/nmat2007. PMID 17828278.
  7. ^ "Humboldtine".
  8. ^ a b "List of Minerals". 21 March 2011.
  9. ^ "Stepanovite".
source: https://en.wikipedia.org/wiki/Ferrous_oxalate