Iron(III) bromide

Iron(III) bromide

Names
IUPAC name Iron(III) bromide
Other names Ferric bromide Iron tribromide tribromoiron
Identifiers
CAS Number	10031-26-2 Y
ECHA InfoCard	100.030.069
PubChem CID	25554
CompTox Dashboard (EPA)	DTXSID40894107
Properties
Chemical formula	FeBr3
Molar mass	295.56 g mol−1
Appearance	brown solid
Odor	odorless
Density	4.50 g cm−3
Melting point	200 °C (decomposes)
Structure
Crystal structure	Trigonal, hR24
Space group	R-3, No. 148
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	corrosive
NFPA 704 (fire diamond)	3 0 0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Iron(III) bromide is the chemical compound with the formula FeBr₃. Also known as ferric bromide, this red-brown odorless compound is used as a Lewis acid catalyst in the halogenation of aromatic compounds. It reacts with water to give acidic solutions.

Structure, synthesis and basic properties

FeBr₃ forms a polymeric structure featuring six-coordinate, octahedral Fe centers. Although inexpensively available commercially, FeBr₃ can be prepared by treatment of iron metal with bromine:

2 Fe + 3 Br₂ → 2 FeBr₃

Above 200 °C, FeBr₃ decomposes to ferrous bromide:

2FeBr₃ → 2FeBr₂ + Br₂

Iron(III) chloride is considerably more stable, reflecting the greater oxidizing power of chlorine. FeI₃ is not stable, as iron(III) will oxidize iodide ions.

See also

• Iron(II) bromide, the lower bromide of iron