Iron(II) acetate

Iron(II) acetate describes compounds with formula Fe(CH₃CO₂)₂·(H₂O)_x where x can be 0 (anhydrous) or 4 (tetrahydrate). The anhydrous compound is a white solid, although impure samples can be slightly colored.^[1] The tetrahydrate is light green solid that is highly soluble in water.

Iron(II) acetate

Names
IUPAC name Iron(II) acetate
Other names Ferrous acetate
Identifiers
CAS Number	3094-87-9 19807-28-4 tetrahydrate
3D model (JSmol)	coordination form: Interactive image ionic form: Interactive image
ChemSpider	17323 Y
ECHA InfoCard	100.019.492
PubChem CID	18344
RTECS number	AI3850000
UNII	L80I7M6D3Q Y
CompTox Dashboard (EPA)	DTXSID5037656
InChI InChI=1S/2C2H4O2.Fe/c2*1-2(3)4;/h2*1H3,(H,3,4);/q;;+2/p-2 Y Key: LNOZJRCUHSPCDZ-UHFFFAOYSA-L Y InChI=1/2C2H4O2.Fe/c2*1-2(3)4;/h2*1H3,(H,3,4);/q;;+2/p-2 Key: LNOZJRCUHSPCDZ-NUQVWONBAS
SMILES coordination form: CC(O1)O[Fe]12OC(O2)C ionic form: CC(=O)[O-].[Fe+2].CC(=O)[O-]
Properties
Chemical formula	C4H6FeO4
Molar mass	173.933 g·mol−1
Appearance	White crystals (anhydrous) Light green crystals (tetrahydrate)
Odor	Odorless
Density	1.734 g/cm3 (−73 °C)[1]
Melting point	190–200 °C (374–392 °F; 463–473 K) decomposes[2][3]
Solubility in water	Soluble[2]
Structure
Crystal structure	Orthorhombic, oP75 (200 K)
Space group	Pbcn, No. 60 (200 K)[1]
Point group	2/m 2/m 2/m (200 K)
Lattice constant	a = 18.1715(4) Å, b = 22.1453(5) Å, c = 8.2781(2) Å (200 K) α = 90°, β = 90°, γ = 90°
Hazards
GHS labelling:
Pictograms	[3]
Signal word	Warning
Hazard statements	H315, H319, H335[3]
Precautionary statements	P261, P305+P351+P338[3]
NFPA 704 (fire diamond)	[4] 2 0 0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Preparation and structure

Although anhydrous ferrous acetate can be viewed as a simple salt, X-ray crystallography reveals a complicated polymeric structure.^[1] Color code: red = O, blue = Fe, gray = C, white = H.

Iron powder reacts with acetic acid to give the ferrous acetate, with evolution of hydrogen gas:^[5][1]

Fe + 2 CH₃CO₂H → Fe(CH₃CO₂)₂ + H₂

Reaction of scrap iron with acetic acid affords a brown mixture of various iron(II) and iron(III) acetates that are used in dyeing.^[6]

It can also be made from the insoluble, olive green, Iron(II) carbonate.^{[citation needed]}

It adopts a polymeric structure with octahedral Fe(II) centers interconnected by acetate ligands. It is a coordination polymer.^[1]

Uses

Ferrous acetate is used as a mordant by the dye industry. Ebonizing wood is one such process.^[7]

References

1. Weber, Birgit; Betz, Richard; Bauer, Wolfgang; Schlamp, Stephan (2011). "Crystal Structure of Iron(II) Acetate". Zeitschrift für anorganische und allgemeine Chemie. 637: 102–107. doi:10.1002/zaac.201000274.
2. Lide, David R., ed. (2009). CRC Handbook of Chemistry and Physics (90th ed.). Boca Raton, Florida: CRC Press. ISBN 978-1-4200-9084-0.
3. Sigma-Aldrich Co., Iron(II) acetate. Retrieved on 2014-05-03.
4. "MSDS of Ferrous acetate". fishersci.ca. Fair Lawn: Fisher Scientific. Retrieved 2014-08-02.
5. "Synthesis of Iron(II) acetate hydrate (ferrous acetate)". Archived from the original on 2013-08-25. Retrieved 2009-01-07.
6. Wildermuth, Egon; Stark, Hans; Friedrich, Gabriele; Ebenhöch, Franz Ludwig; Kühborth, Brigitte; Silver, Jack; Rituper, Rafael (2000). "Iron Compounds". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a14_591. ISBN 978-3527306732.
7. Ebonizing Wood with Ferric Acetate