| From Wikipedia, the free encyclopediaTerbium is a chemical element with symbol Tb and atomic number 65. It is a silvery-white rare earth metal that is malleable, ductile and soft enough to be cut with a knife. Terbium is never found in nature as a free element, but it is contained in many minerals, including cerite, gadolinite, monazite, xenotime and euxenite. | |||||||||
Terbium in the periodic table | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Symbol | Tb | ||||||||
| Atomic number | 65 | ||||||||
| Group | 0 | ||||||||
| Period | 6 | ||||||||
| Block | f | ||||||||
| Element category | Lanthanide | ||||||||
Physical properties | |||||||||
| Phase at STP | Solid | ||||||||
| Density | 8.23 g/cm3 | ||||||||
| Atomic weight | 158.925 u | ||||||||
| Melting point | 1629 K 1355.85 °C 2472.53 °F | ||||||||
| Boiling point | 3396 K 3122.85 °C 5653.13 °F | ||||||||
Atomic properties | |||||||||
| Electronegativity (Pauling Scale) | 1.1 | ||||||||
| Electron affinity | 112.4 kJ/mol | ||||||||
| Oxidation states | 0, +1, +2, +3, +4 (a weakly basic oxide) | ||||||||
| Ionization energies |
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Electron configuration | |||||||||
| Elektronkonfiguration (shorthand) | [Xe] 4f9 6s2 | ||||||||
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f9 5s2 5p6 6s2 | ||||||||
| Electrons per shell | 2, 8, 18, 27, 8, 2 | ||||||||
History | |||||||||
| Discovered | 1843 | ||||||||
| Discovered by | Carl Gustaf Mosander | ||||||||