The Iron (III) oxide reference article from the English Wikipedia on 24-Jul-2004
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Iron (III) oxide

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Name Iron (III) oxide
Chemical formula Fe2O3
Appearance Red powder


Formula weight 159.7 amu
Melting point 1838 K (1565 °C)
Density 5.2 ×103 kg/m3
Crystal structure Corundum
Solubility insoluble


ΔfH0liquid ? kJ/mol
ΔfH0solid -824 kJ/mol
S0liquid, 1 bar ? J/mol·K
S0solid 87 J/mol·K


Ingestion Extremely large or sustained doses may cause iron poisoning.
Inhalation Dust may cause mechanical irritation. Long term exposure to dust may cause mild pneumoconiosis.
Skin No adverse effect reported.
Eyes May cause mechanical irritation. Long term exposure may stain the cornea.
More info Hazardous Chemical Database
SI units were used where possible. Unless otherwise stated, standard conditions were used.

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Iron (III) oxide, also known as ferric oxide, red iron oxide or synthetic maghemite, is one of several oxide compoundss of iron, and is most notable for its ferromagnetic properties. Its chemical formula is Fe2O3.

The mineral form of ferric oxide is hematite; it is mined as the main ore of iron.

Iron (III) oxide is often used in magnetic storage, for example in the magnetic layer of floppy disks. These consist of a thin sheet of mylar plastic, coated with Iron (III) oxide. The particles can be magnetised to represent binary data. Magnetic Ink Character Recognition also uses Iron (III) oxide compounds, suspended in an ink which can be read by special scanning hardware.

The CAS number of ferric oxide is 1309-37-1.

See also