58Ce140.116
Cerium
Lanthanoids · solid at STP · Block F
About
Cerium is a soft, silvery-white metal and the most abundant of the rare-earth elements, making up a significant portion of ores like monazite. It is a key component in the 'flint' of lighters (ferrocerium). Its oxide is a highly effective abrasive used for precision polishing of glass and lenses. It also acts as a catalyst in self-cleaning ovens and diesel fuel additives.
Atomic Properties
Atomic Number58
Atomic Weight140.116 u
Neutrons (common)82
Electron Configuration[Xe] 4f¹ 5d¹ 6s²
Full Configuration1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹ 5s² 5p⁶ 5d¹ 6s²
Electrons per Shell2, 8, 18, 19, 9, 2
Electronegativity1.12
Electron Affinity55 kJ/mol
Oxidation States+4, +3
Covalent Radius182 pm
Ionic Radius102 pm
Periodic Table Position
Group3
Period6
BlockF
Chemical SeriesLanthanoids
Physical Properties
State at STPsolid
Appearancesilvery-white
Crystal Structurefcc
Magnetic Orderingparamagnetic
Speed of Sound2,100 m/s
Poisson Ratio0.24
Thermal Properties
Melting Point1,068 K
Boiling Point3,716 K
Thermal Expansion0 1/K
Thermal Conductivity11.3 W/(m·K)
Specific Heat0.192 J/(g·K)
Molar Heat26.94 J/(mol·K)
Heat of Fusion5.46 kJ/mol
Heat of Vaporization398 kJ/mol
Abundance
In Earth's Crust66.5 ppm
In Ocean0 ppm
In Solar System0.004 ppm
In Universe0.01 ppm
Discovery
Discovered byMartin H. Klaproth, Jöns J. Berzelius, Wilhelm Hisinger
Discovery Year1,803
Occurrenceprimordial
CAS Number7440-45-1
Electron Configuration
Energy
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6p
7s
5f
6d
7p
Isotopes of Cerium
| Symbol ▲ | Mass (u) ▲ | Abundance ▲ | Half-life ▲ | Decay Mode ▲ |
|---|---|---|---|---|
| 136Ce | 135.907170 | 0.186% | Stable | Stable |
| 138Ce | 137.905990 | 0.251% | Stable | Stable |
| 140Ce | 139.905440 | 88.449% | Stable | Stable |
| 142Ce | 141.909240 | 11.114% | 44 Py | Double Beta Minus Decay |
Interactive Visualization
Explore the 3D Bohr model of Cerium in our interactive viewer.
View 3D Model of Cerium