Cerium

Element 58 on the periodic table, symbol Ce, group 3, period 6.

Cerium 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).

Appearance: silvery white

Properties

Atomic Number: 58
Atomic Mass: 140.1161 u
Group: 3
Period: 6
Block: f-block
Category: Lanthanide
State at 25 °C: Solid
Melting Point: 1,068 K · 794.9 °C
Boiling Point: 3,716 K · 3,442.9 °C
Density: 6.77 g/cm³
Atomic Radius: 185 pm
Electronegativity: 1.12
Oxidation States: +3, +4
Abundance in Crust: 66.5 mg/kg
Discovered: 1803
Discovered By: Martin Heinrich Klaproth

Electron Configuration

[Xe] 4f1 5d1 6s2

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

Ionisation Energies (kJ/mol)

1. 534.4
2. 1,050
3. 1,949
4. 3,547
5. 6,325
6. 7,490

Elements near Cerium

Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.