68 Er 167.26
Erbium
Lanthanide
Erbium (Er) is a chemical element with atomic number 68, classified as a lanthanide. At room temperature it is a solid. It was discovered in 1843 by Carl Gustaf Mosander.
Properties
- Atomic number
- 68
- Atomic mass
- 167.26 u
- Category
- Lanthanide
- Group
- 0
- Period
- 6
- Block
- f-block
- Electron configuration
- [Xe] 4f¹² 6s²
- Phase at STP
- Solid
- Density
- 9.066 g/cm³
- Melting point
- 1802 K (1528.8 °C)
- Boiling point
- 3141 K (2867.8 °C)
- Electronegativity
- 1.24
- Atomic radius
- 226 pm
- Ionization energy
- 6.108 eV
- Discovery
- 1843 · Carl Gustaf Mosander
Common uses
Fiber optic cables, lasers, nuclear technology, photography
Did you know?
Essential for internet fiber optic communications worldwide.