What Is Cerium?
Cerium, with the symbol Ce and atomic number 58, is a silvery-white lanthanide and the most abundant rare earth element, found mainly in the minerals monazite and bastnasite. It exhibits valences of +2, +3, and +4, with the +4 state being more common in its compounds, which are notable for their ability to absorb ultraviolet light.
Uses of Cerium
Commercially, cerium is used in UV-blocking glass, glass polishes, and as an alloy in lighter flints. Its oxides enhance the performance of catalytic converters, and its compounds are used in fluorescent materials for LEDs and cathode ray tubes.
Properties of Cerium
Cerium is a reactive metal, easily oxidizing in air to form cerium oxide and spontaneously igniting at 160°C. It reacts with water to produce cerium (III) hydroxide and dissolves in acids, forming colorless Ce(III) ions. The metal’s melting point is 795°C, and its boiling point is 3,443°C.
Structure of Cerium
At room temperature, cerium adopts a face-centered cubic structure, shifting to a body-centered cubic form above 730°C, and possesses a hexagonal close-packed structure at lower temperatures. Its density near room temperature is 6.770 g/cm3.
Other Information on Cerium
1. Production of Cerium
Primarily refined from bastnasite and monazite, cerium production is concentrated in China, with significant reserves in the United States and India. Cerium compounds and metals are produced through various chemical and electrolytic processes.
2. Isotopes of Cerium
Cerium has four stable isotopes and numerous radioactive isotopes, the most abundant of which is 140Ce. The isotopes 144Ce, 139Ce, and 141Ce are notable for their relatively longer half-lives among the radioactive varieties.