Chromium (III) oxide. Inorganic compound. It is one of the main oxides of chromium and is used as a pigment. In nature, it is found in eskolite, a rare mineral. Cr 2 O 3
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- 1 Features
- 2 Obtaining
- 3 Properties
- 4 Uses
- 5 Care
- 6 External links
- 7 Sources
Chromium (III) oxide or chromic oxide is a chemical compound whose formula is (Cr 2 O 3 ) considered one of the most important chromium oxides. It can be found in nature in the form of a mineral.
Chromium (III) oxide is a metallic oxide formed by:
- 2 chromiumatoms .
- 3 oxygenatoms .
Cr 2 O 3 occurs naturally in the Slakoite mineral, which is found in chromium-rich tremolite skarns, metaquartzites, and chlorite veins. Eskolaite is also a rare component of chondrite meteorites. The mineral is named after the late geologist Pentti Eskola.
The main properties of chromic oxide (Cr 2 O 3 ) are:
- Density: 5.22 g / cm3.
- Melting point: 2435 ° C.
- Molar mass: 151.9904 g / mol.
- Boiling point: 4000 ° C.
Among the most common uses of chromium (III) oxide are:
- Elaboration of paintings.
- Green pigment.
- Used in polishing materials.
Due to its great stability, it is a commonly used pigment and was originally called Viridian. It is used in paints, inks, and glasses. It is the coloring in “chrome green” and “institutional green”. It is the precursor of the chromium dioxide magnetic pigment, according to the following reaction:
Cr 2 O 3 + 3 CrO 3 = 5 CrO 2 + O 2
It is one of the materials used to polish the edges of blades on a piece of leather (also called sharpening). In this context, it is often known as a green compound.
Absolutely avoid breathing chrome oxide dust , avoid contact with eyes , skin and clothing; You have to keep the packages tightly closed and wash your hands well after handling.