Cerium (Ce)

Cerium is a chemical element of the periodic table with chemical symbol Ce and atomic number 58 with an atomic weight of 140.116 u and is classed as lanthanide. Cerium is solid at room temperature.

Lanthanum Periodic table Praseodymium

Cerium in the periodic table

Symbol	Ce
Atomic number	58
Group	-
Period	6
Block	f
Classification	Lanthanide

Appearance	Silvery white
Color	Silver

Number of protons	58 p⁺
Number of neutrons	82 n⁰
Number of electrons	58 e^-

From Wikipedia, the free encyclopediaCerium is a chemical element with symbol Ce and atomic number 58. It is a soft, silvery, ductile metal which easily oxidizes in air. Cerium was named after the dwarf planet Ceres (itself named after the Roman goddess of agriculture).

Physical properties

Phase at STP	Solid
Density	6.77 g/cm³
Atomic weight	140.116 u

Thermal properties

Melting point	1068 K 794.85 °C 1462.73 °F
Boiling point	3716 K 3442.85 °C 6229.13 °F
Heat of vaporization	313.8 kJ/mol

Atomic properties

Electronegativity (Pauling Scale)	1.12
Electron affinity	55 kJ/mol
Oxidation states	+1, +2, +3, +4 (a mildly basic oxide)
Ionization energies	534.4 kJ/mol 1050 kJ/mol 1949 kJ/mol 3547 kJ/mol 6325 kJ/mol 7490 kJ/mol

Electron configuration for cerium

Electron configuration

Shorthand configuration

[Xe] 4f¹ 5d¹ 6s²

Electron configuration

Full configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹ 5s² 5p⁶ 5d¹ 6s²

Electron configuration chart

1s²
2s²	2p⁶
3s²	3p⁶	3d¹⁰
4s²	4p⁶	4d¹⁰	4f¹
5s²	5p⁶	5d¹
6s²

Electrons per shell

2, 8, 18, 19, 9, 2

Valence electrons

2

Valency electrons

4

Bohr model

Figure: Shell diagram of Cerium (Ce) atom.

Orbital Diagram

1s

2s

2p

3s

3p

3d

4s

4p

4d

4f

5s

5p

5d

6s

The history of Cerium

Discovery	Martin Heinrich Klaproth, Wilhelm Hisinger, Jöns Jacob Berzelius (1803)
First isolation	Carl Gustaf Mosander (1838)
Named by	Jöns Jacob Berzelius
Discovery of cerium Cerium was discovered in Bastnäs in Sweden by Jöns Jakob Berzelius and Wilhelm Hisinger, and independently in Germany by Martin Heinrich Klaproth, both in 1803. Cerium was named by Berzelius after the asteroid Ceres, discovered two years earlier. The asteroid is itself named after the Roman goddess Ceres, goddess of agriculture, grain crops, fertility and motherly relationships. Cerium was originally isolated in the form of its oxide, which was named ceria, a term that is still used. Ceria, as isolated in 1803, contained all of the lanthanides present in the cerite ore from Bastnäs, Sweden, and thus only contained about 45% of what is now known to be pure ceria. It was not until Carl Gustaf Mosander succeeded in removing lanthana and "didymia" in the late 1830s that ceria was obtained pure.

Periodic table history

Identifiers

List of unique identifiers for Cerium in various chemical registry databases

CAS Number	7440-45-1
ChemSpider ID	22411
EC number	231-154-9
PubChem CID Number	23974