Ferrous oxalate dihydrate

Synonym(s):Ferrous oxalate dihydrate

CAS NO.：6047-25-2
Empirical Formula: C2H2FeO6
Molecular Weight: 177.88
MDL number: MFCD00150040
EINECS: 611-981-5
SAFETY DATA SHEET (SDS)
Update Date: 2026-01-13 11:17:15

What is Ferrous oxalate dihydrate?

Description

Iron(II) oxalate, FeC204.2H20, is precipitated as yellow crystals from solutions containing iron(II) and oxalate ions ; in the presence of excess alkali metal oxalate, however, soluble oxalato complexes M2[Fe(C2O4)2] are formed which can be precipitated by the addition of alcohol. The oxalate is paramagnetic with μeff= 5·2 B.M. at room temperature.

Chemical properties

yellow powder
Ferrous oxalate, or iron(II) oxalate, is a chemical compound consisting of one iron(II) ion (Fe2) and one oxalate ion (C2O4(2−)). It has the chemical formula FeC2O4. Iron(II) oxalate is more commonly encountered as the dihydrate, FeC2O4·2H2O, CAS # 6047-25-2. Its crystal structure consists of chains of oxalate-bridged iron atoms, capped by water molecules. When heated, it dehydrates and decomposes into carbon dioxide, carbon monoxide, iron oxides and pyrophoric black iron.

The Uses of Ferrous oxalate dihydrate

It is used as photographic developer for silver bromide-gelatin plates. It imparts greenish-brown tint to optical glass (sunglasses, windshields, railroad car windows), for decorative glassware, pigment for plastics, paints and lacquers. It acts as reagent.

Properties of Ferrous oxalate dihydrate

Melting point:	190°C (dec.)
Density	2.28 g/mL at 25 °C(lit.)
solubility	soluble in acid solutions
form	Powder
color	yellow
Specific Gravity	2.28
Water Solubility	Soluble in water. Insoluble in acetic acid.
Sensitive	Hygroscopic
Solubility Product Constant (Ksp)	pKsp: 6.5
BRN	3757620
Exposure limits	ACGIH: TWA 1 mg/m3 NIOSH: TWA 1 mg/m3
Stability:	Stable. Hygroscopic. Incompatible with strong oxidizing agents.
CAS DataBase Reference	6047-25-2(CAS DataBase Reference)
EPA Substance Registry System	Iron, diaqua[ethanedioato(2-)-.kappa.O1,.kappa.O2]-, (T-4)- (6047-25-2)

Safety information for Ferrous oxalate dihydrate

Signal word	Warning
Pictogram(s)	Exclamation Mark Irritant GHS07
Precautionary Statement Codes	P264:Wash hands thoroughly after handling. P264:Wash skin thouroughly after handling. P270:Do not eat, drink or smoke when using this product. P280:Wear protective gloves/protective clothing/eye protection/face protection. P301+P312:IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.