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Your current location :Home > Chromium oxide - Cr2O3

Chromium Oxide (Cr2O3)

Chromium(III) oxide is the inorganic compound of the formula Cr2O3. It is one of principal oxides of chromium and is used as a pigment. In nature, it occurs as the rare mineral eskolaite.

Cr2O3 adopts the corundum structure, consisting of a hexagonal close packed array of oxide anions with 2/3 of the octahedral holes occupied by chromium. Similar to corundum, Cr2O3 is a hard, brittle material (Mohs hardness 8-8.5). It is antiferromagnetic up to 307 K, the Neel temperature.It is not readily attacked by acids or bases, although molten alkali gives chromates (salts with the CrO2−4 anion, not to be confused with the related mineral chromite). It turns brown when heated, but reverts to its dark green color when cooled. It is also hygroscopic.

Because of its considerable stability, chromia is a commonly used pigment and was originally called viridian. It is used in paints, inks, and glasses. It is the colourant in "chrome green" and "institutional green." Chromium(III) oxide is a precursor to the magnetic pigment chromium dioxide, according to the following reaction: 

Cr2O3 + 3 CrO3 → 5 CrO2 + O2

It is one of the materials that are used when polishing (also called stropping) the edges of knives, razors, etc. on a piece of leather, balsa, cloth, or other material. In this context it is alternatively known as "green compound".

Basic Infomation

CAS Registry Number:1308-38-9 

ChEBI CHEBI:48242 

ChemSpider: 451305 

PubChem:517277

RTECS number: GB6475000

UNII: X5Z09SU859 

Chemical formula:Cr2O3

Molar mass:151.9904 g/mol

Appearance:light to dark green, fine crystals

Density: 5.22 g/cm3

Melting point: 2,435 °C (4,415 °F; 2,708 K)

Boiling point: 4,000 °C (7,230 °F; 4,270 K)

Solubility in water:insoluble

Solubility in alcohol: insoluble in alcohol, acetone, acids

Refractive index (nD):2.551

Crystal structure:hexagonal

Thermochemistry Std molar entropy (So298):81 J·mol−1·K−1

Std enthalpy of formation (ΔfHo298):−1128 kJ·mol−1

Cr2O3 Sputtering targetChromium Oxide Sputtering Target - Cr2O3

Purity--- 99.9%

Density---5.2 g/ cm3

Refractive Index/Transparence Wave Band--- 2.4

Shape--- Discs, Plate, Step (Dia ≤480mm,,  Thickness ≥1mm)

                Rectangle, Sheet,  Step (Length ≤400mm, Width ≤300mm, Thickness ≥1mm)

Application --- Absorbent brown film with medium index.

Chromium Oxide Evaporation Material - Cr2O3

  • Purity---99.9%
  • Shape---Granule
  • Dimension---1-6mm
  • Application---

Chromium Oxide Powder - Cr2O3

  • Purity---99.9%
  • Dimension--- 150mesh,300mesh,250mesh
  • Application---

Relation Pruducts

Chromium Sputtering Targets - Cr

Chromium Boride Sputtering targets - CrB2 / CrB;

Chromium Carbide Sputtering Targets - Cr3C2;

Chromium Oxide Sputttering Targets - Cr2O3;

Chromium Silicon Sputtering targets - CrSi2 / CrSi;

Chromium doped Silicon monoxide - Cr+SiO;

 

 

 

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