Cerium
Silvery metallic element, belongs to the lanthanoids. Four natural isotopes exist, and fifteen radioactive isotopes have been identified. Used in some rare-earth alloys. The oxidized form is used in the glass industry. Discovered by Martin .H. Klaproth in 1803.
Gallery
Jurii, CC BY 1.0 <https://creativecommons.org/licenses/by/1.0>, via Wikimedia Commons, source: https://images-of-elements.com/cerium.php
Physical Propertiesmass · density · phase · crystal
Atomic Mass
140.1160Da
Density
6.7700g/cm³
Phase (STP)
Solid
Melting Point
1072.2K
Boiling Point
3716.2K
Molar Heat
0.1920J/(mol·K)
Crystal Structure
FCC
Lattice Constant
5.160Å
Atomic Radiiatomic · covalent · van der Waals
Atomic (Empirical)
185.00pm
Covalent
163.00pm
Van der Waals
242.00pm
Electronic Propertieselectronegativity · ionization · affinity
Electron Configuration
[Xe] 4f 5d 6s2
Electron Shells
2, 8, 18, 19, 9, 2
Electronegativity
1.12Pauling
Electron Affinity
0.7kJ/mol
1st Ionization Energy
5.5kJ/mol
Oxidation States
+2, +3, +4
Orbital DiagramAufbau · Hund's rule · Pauli exclusion
Full: 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f1 5d1 6s2Short: [Xe] 4f 5d 6s2
Ionization Energies (58 known)
Emission Spectrumvisible range · characteristic spectral lines
Abundanceby mass
Log scale · ppm = parts per million by mass
Biological Role
No known biological role. Cerium oxide nanoparticles studied as antioxidants.
Discovery
Discovered By
W. von Hisinger, J. Berzelius, M. Klaproth
Named By
—
Year
1803
Nuclear Data
Known Isotopes
41
Stable Isotopes
5
Stable Mass Numbers
136, 138, 140, 142, 159
Natural isotopic abundance (IUPAC recommended values)
Isotopes of Ce41 known
| Nuclide | Z | N | Mass (AMU) | Half-life | Decay | Jπ | Abundance |
|---|---|---|---|---|---|---|---|
| 119Ce | 58 | 61 | 118.952957 | Unknown | β⁺, β⁺p | 5/2+ | — |
| 120Ce | 58 | 62 | 119.946613 | Unknown | β⁺, β⁺p | 0+ | — |
| 121Ce | 58 | 63 | 120.943435 | 1.10 s | β⁺ (1%), β⁺p (0.01%) | 5/2 | — |
| 136Cestable | 58 | 78 | 135.907129 | Stable | 2β⁺ | 0+ | 18.6000% |
| 138Cestable | 58 | 80 | 137.905994 | Stable | 2β⁺ | 0+ | 25.1000% |
| 140Cestable | 58 | 82 | 139.905448 | Stable | stable (1%) | 0+ | 8844.9000% |
| 142Cestable | 58 | 84 | 141.909250 | Stable | α, 2β⁻ | 0+ | 1111.4000% |
| 157Ce | 58 | 99 | 156.957133 | 175 ms | β⁻ (1%), β⁻n | 7/2+ | — |
| 158Ce | 58 | 100 | 157.960773 | 99.0 ms | β⁻ (1%), β⁻n | 0+ | — |
| 159Cestable | 58 | 101 | 158.966355 | Stable | β⁻, β⁻n | 1/2- | — |