65Tb158.93
Terbium (Tb)
Element 65 · Lanthanide
Terbium (Tb) is a chemical element with atomic number 65. It is classified as a lanthanide in period 6 of the periodic table (the f-block). Its standard atomic weight is 158.93 u and its ground-state electron configuration is [Xe] 4f⁹ 6s².
Terbium facts
| Atomic number (Z) | 65 |
|---|---|
| Symbol | Tb |
| Standard atomic weight | 158.93 u |
| Category | Lanthanide |
| Group | — (f-block) |
| Period | 6 |
| Block | f-block |
| Electron configuration | [Xe] 4f⁹ 6s² |
| Electronegativity (Pauling) | 1.2 |
| State at 20 °C | Solid |
| Protons / electrons | 65 / 65 |
| Neutrons (most common isotope, approx.) | 94 |
| Molar mass | 158.93 g/mol |