Stable isotopes of cerium available from ISOFLEX
|Isotope||Z(p)||N(n)||Atomic Mass||Natural Abundance||Enrichment Level||Chemical Form|
Cerium was discovered in 1803 by Wilhelm von Hisinger, Jöns Jakob Berzelius and Martin Heinrich Klaproth. It is named after the asteroid Ceres, which had been discovered just two years earlier.
Cerium is a grayish lustrous metal that is malleable and has four allotropic modifications. The common γ-form occurs at ordinary temperatures and atmospheric pressures. The β-form occurs at -16 ºC, the α-form occurs below -172 ºC, and the δ-form occurs at elevated temperatures above 725 ºC. Cerium reacts with water, while the metal is stable in dry air at ordinary temperatures.
Compounds of cerium have many important industrial applications as catalysts, especially in the glass industry. Misch metal, an alloy of cerium with other lanthanides, is a pyrophoric substance and is used to make gas lighters and ignition devices. Some other applications of the metal or its alloys are in solid-state devices, rocket propellant compositions, as a getter in vacuum tubes, and as a diluent for plutonium in nuclear fuel.
Properties of Cerium
|Standard state||Solid at 298 °K|
|CAS Registry ID||7440-45-1|
|Group in periodic table||N/A|
|Period in periodic table||6|
|Block in periodic table||f-block|
|Melting point||799 °C|
|Boiling point||3426 °C|
|Vaporization point||3434 ºC|
|Thermal conductivity||11 W/(m·K)|
|Electrical resistivity||75.0 µΩ·cm at 25 °C|
|Specific heat||192 J/kg K|
|Heat of vaporization||350 kJ·mol-1|
|Heat of fusion||5.5 kJ·mol-1|
|Density of liquid||6.55 g/cm3 at 799 °C|
|Density of solid||6.77 g/cm3|
|Metallic radius (alpha form)||1.8247 Å (coordination number 12)|
|Atomic volume||20.696 cm3/mol|
|Common oxidation states||+3, +4|