Cerium(IV) oxide, also called ceria or cerium dioxide, is a chemical compound made of cerium and oxygen. It has the chemical formula CeO2. It is white or light yellow in color. It is an important commercial product. It is used as an intermediate to make pure cerium from ores.
Cerium(IV) oxide can be made by the oxidation of cerium(III) oxide. Also, it can be made by heating cerium(IV) hydroxide.[source?]
It can also be made by heating cerium(IV) oxalate (chemically called thermolysis or calcination).
Cerium dioxide was added to gas mantles to make them brighter. Gas mantles were used for streetlights in the 19th century, before electric lighting was available.
Cerium dioxide is a mild oxidizing agent through reduction to cerium(III) oxide, Ce2O3. For example, it oxidizes carbon monoxide:
This reaction is used in catalytic converters. It can be used in oxidation of natural gas.