Chromium(VI) oxide (CrO3)-Crystal

Characteristic




Chromium(VI) oxide, also known as chromium trioxide, is a chemical compound. Its chemical formula is CrO3.It has chromium in its +6 oxidation state. It also has oxide ions. It is a solid used in cleaning glass. Chromium-6 is odorless and tasteless.




Chemical formula:CrO3

Molar mass:99.993 g·mol−1

Appearance:Dark red granular solid, deliquescent

Odor:Odorless

Density:2.7 g/cm3 (20 °C)

Melting point:197 °C (387 °F; 470 K) 

Boiling point:250 °C (482 °F; 523 K) decomposes

Solubility in water:164.8 g/100 mL (0 °C)；169 g/100 mL (25 °C)；172.6 g/100 mL (40 °C)；198.1 g/100 mL (100 °C)

Solubility:Soluble in H2SO4, HNO3, (C2H5)2O, CH3COOH, acetone

Magnetic susceptibility (χ):+40·10−6 cm3/mol




Application




Chromium trioxide is mainly used in chrome plating. It is typically employed with additives that affect the plating process but do not react with the trioxide. The trioxide reacts with cadmium, zinc, and other metals to generate passivating chromate films that resist corrosion. It is also used in the production of synthetic rubies. Chromic acid solution is also used in applying types of anodic coating to aluminium, which are primarily used in aerospace applications. A chromic acid/phosphoric acid solution is also the preferred stripping agent of anodic coatings of all types.