68 - Erbium lanthanide
Discovered by Carl Gustaf Mosander in 1843
- Atomic Radius (Å)
Erbium is a chemical element in the lanthanide series, with symbol Er and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements on Earth. As such, it is a rare earth element which is associated with several other rare elements in the mineral gadolinite from Ytterby in Sweden, where yttrium, ytterbium, and terbium were discovered.
Shell | Electrons | Orbitals |
---|---|---|
1 | 2 | 2 in 1s |
2 | 8 | 2 in 2s + 6 in 2p |
3 | 18 | 2 in 3s + 6 in 3p + 10 in 3d |
4 | 30 | 2 in 4s + 6 in 4p + 10 in 4d + 12 in 4f |
5 | 8 | 2 in 5s + 6 in 5p |
6 | 2 | 2 in 6s |
167.26 u
Atomic Mass
2.5 Å
Atomic Radius
3503 K
Boiling Point
1.89 Å
Covalent Radius
9.07 g/cm³
Density
30.1
Electron Affinity
1.24
Electronegativity
6.11 eV
First Ionization Energy
1795.15 K
Melting Point
6
Number of Shells
68
Atomic Number
2, 8, 18, 30, 8, 2
Electron Shell Occupations