What is Chromic oxide?

Cr2O3 is an inorganic compound v chemical name Chromic oxide. It is also called Dichromium trioxide, or Chromium (3+) oxide, or Chromium (III) oxide. It naturally occurs in a mineral eskolaite, which is mostly discovered in chromium-rich skarns, tremolite, chlorite veins, and also meta quartzites. Chromium (III) oxide shows up as a fine light to dark green, hexagonal crystal. The is amphoteric and also insoluble in water.

You are watching: Oxidation number of chromium in cr2o3

Properties of Chromic oxide – Cr2O3

Cr2O3Chromic oxide
Molecular weight of Cr2O3151.9904 g/mol
Density the Chromic oxide5.22 g/cm3
Boiling point of Chromic oxide4,000 °C
Melting allude of Chromic oxide2,435 °C

Chromic oxide framework – Cr2O3


The specific mass and also the monoisotopic mass of Chromium (3+) oxide is 151.866 g/mol. The variety of hydrogen bond acceptors equals to three and also the variety of hydrogen bond donors equates to to zero. This link is canonicalized and has five covalently external inspection unit.

Cr2O3 uses (Chromic oxide)

Chromic oxide is used in electrical semiconductors.Used in the colouring glass.Used in cultivating senescence.Used in dyeing polymers.Used in the manufacturing of chromium metal.Used as a catalyst to prepare butadiene.Used in stainless steel polishing.Used as an anaesthetic.Used to add colours in drugs.Used in welding metals.

Production of Chromic oxide

In the year 1838, the Parisians Pannetier and also Binet prepared the transparent hydrated kind of Chromium (III) oxide. That is acquired from the mineral chromite. The counter of chromite to chromia is as follows:

Na2Cr2O7 + S → Na2SO4 + Cr2O3

The oxide can additionally be do by decomposing chromium salt or by exothermically decomposing ammonium dichromate.

(NH4)2Cr2O7 → Cr2O3 + N2 + 4 H2O

Chemical reactions:

Dichromium trioxide when heated with finely divided aluminium or carbon reduces to chromium metal. The reaction is together follows:

Cr2O3 + 2Al → 2Cr + Al2O3

Heating Chromium (III) oxide through carbon and chlorine offers CrCl3 and also carbon monoxide (CO):

Cr2O3 + 3Cl2 + 3C → 2CrCl3 + 3CO

Oxidation the chromium (III) oxide results in chromates:

2Cr2O3 + 4MO + 3O2 → 4MCrO4

Frequently inquiry Questions

Is chromic oxide acidic or basic?

Chromic oxide (or chromium(III) oxide) is one amphoteric compound. It has the capability to dissolve in acids, liberating sign language chromium ions in the process. These hydrated Cr ions deserve to react with bases come form complex salts.

What is chromic oxide used for?

This link is an extremely useful in the process of stropping knife edges. It is also used for polishing the surface of optical devices and also for the dyeing the polymers.

What is the complete charge ~ above the Cr2O3 molecule?

The two chromium cations organize a fee of +3 each, amounting come a total of +6. Every oxygen ion hold a fee of -2, totalling to -6. The ionic compound is, therefore, neutral.

See more: What Is The Value Of A 1941 Wheat Penny Worth? (Price Chart)

Learn an ext about the Structure, physical and chemical nature of Cr2O3 native the professionals at BYJU’S.