Cerium

58
Ce
Group
n/a
Period
6
Block
f
Protons
Electrons
Neutrons
58
58
82
General Properties
Atomic Number
58
Atomic Weight
140.116
Mass Number
140
Category
Lanthanides
Colour
Silver
Radioactive
No
Cerium was named for the asteroid Ceres
Crystal Structure
Simple Hexagonal
History
Jöns Jakob Berzelius and Wilhelm Hisinger discovered the element in ceria in 1803 in Sweden.

Klaproth discovered it simultaneously and independently in some tantalum samples in Germany.

Carl Gustaf Mosander, who worked closely with Berzelius, prepared metallic cerium in 1825.
Electrons per shell
2, 8, 18, 19, 9, 2
Electron Configuration
[Xe] 4f1 5d1 6s2
Ce
Seawater contains 1.5 parts per trillion of cerium
Physical Properties
Phase
Solid
Density
6.77 g/cm3
Melting Point
1068.15 K | 795 °C | 1463 °F
Boiling Point
3716.15 K | 3443 °C | 6229.4 °F
Heat of Fusion
5.5 kJ/mol
Heat of Vaporization
350 kJ/mol
Specific Heat Capacity
0.192 J/g·K
Abundance in Earth's crust
0.006%
Abundance in Universe
1×10-6%
Ultrapure
Image Credits: Images-of-elements
Ultrapure cerium under argon
CAS Number
7440-45-1
PubChem CID Number
23974
Atomic Properties
Atomic Radius
182 pm
Covalent Radius
204 pm
Electronegativity
1.12 (Pauling scale)
Ionization Potential
5.5387 eV
Atomic Volume
20.67 cm3/mol
Thermal Conductivity
0.114 W/cm·K
Oxidation States
2, 3, 4
Applications
Cerium is used in carbon-arc lighting, especially in the motion picture industry.

Cerium oxide is an important component of glass polishing powders and phosphors used in screens and fluorescent lamps.

Cerium compounds are also used in the manufacture of glass, both as a component and as a decolourizer.
Cerium is considered to be moderately toxic
Isotopes
Stable Isotopes
136Ce, 138Ce, 140Ce, 142Ce
Unstable Isotopes
119Ce, 120Ce, 121Ce, 122Ce, 123Ce, 124Ce, 125Ce, 126Ce, 127Ce, 128Ce, 129Ce, 130Ce, 131Ce, 132Ce, 133Ce, 134Ce, 135Ce, 137Ce, 139Ce, 141Ce, 143Ce, 144Ce, 145Ce, 146Ce, 147Ce, 148Ce, 149Ce, 150Ce, 151Ce, 152Ce, 153Ce, 154Ce, 155Ce, 156Ce, 157Ce