| Attribute | Value |
|---|---|
| Symbol | Er |
| Standard state | Solid |
| Atomic mass | 167.26 u |
| Electron configuration | [Xe]6s²4f¹² |
| Oxidation states |
|
| Electronegativity (pauling scale) | 1.24 |
| Atomic radius (van der waals) | 235 pm |
| Ionization energy | 6.108 eV |
| Melting point | 1802 K |
| Boiling point | 3141 K |
| Density | 9.07 g/cm³ |
| Atomic number | 68 |
| Group name | Lanthanide |
| Discovered | 1843 year |
| Electron affinity | Add |