Element Terbium
It is a silvery-white, rare earth metal that is malleable, ductile, and soft enough to be cut with a knife.
Terbium is a chemical element with the symbol Tb and atomic number 65
Terbium is never found in nature as a free element, but it is contained in many minerals, including cerite, gadolinite, monazite, xenotime, and euxenite.
Names and Identifiers
| Chemical Formula: | Tb |
| CAS: | 7440-27-9 |
| Molecular Weight: | 158.925g/mol |
| EC Number : | 231-137-6 |
| MDL Number: | MFCD00011256 |
| Color: | silvery-gray/ silvery white |
| Other Names: | Terbio, Térbio |
| PubChem CID: | 23958 |
| IUPAC Name: | Terbium |
| Inchl: | InChI=1S/Tb |
| InChI Key: | GZCRRIHWUXGPOV-UHFFFAOYSA-N |
| Canonical SMILES: | [Tb] |
| ICSC Number: | n/a |
Physical & Chemical Properties
| Phase: | Solid |
| Density: | 8.23 g/cm³ |
| Boiling Point: | 3396 K (3123 °C, 5653 °F) |
| Melting Point: | 1629 K (1356 °C, 2473 °F) |
| Molecular Formula: | Tb |
| Flash Point: | n/a |
| Exact Mass: | 158.925293 |
| Symbol: |  |
| Signal Word: | Danger |
| Hazard Statements: | H228 |
| Precautionary Statements: | P210 |
| Hazard Codes: | F,T |
| Risk Phrases: | R11-34-23/24/25 |
| Safety Phrases: | S22-S24/25-S36/37/39-S33-S16-S45-S28-S27-S26 |
| RIDADR: | UN 3089 4.1/PG 2 |
| WGK Germany: | 3 |
| RTECS: | n/a |
| Packaging Group: | III |
| Hazard Class: | 8 |
Naturally occurring terbium is composed of its only stable isotope, terbium-159; the element is thus called mononuclidic and monoisotopic.
Naturally occurring isotopes
| Isotope | Mass/Da | Natural abundance (atom %) | Nuclear spin (I) | Magnetic moment (μ/μN) |
|---|---|---|---|---|
| 159Tb | 158.925342 (4) | 100 | 3/2 | 2.014 |
Radiosotope data
| Isotope | Mass/Da | Half-life | Mode of decay | Nuclear spin | Nuclear magnetic moment |
|---|---|---|---|---|---|
| 153Tb | 152.923433 | 2.34 d | EC to 153Gd | 5/2 | 3.5 |
| 154Tb | 153.02469 | 21.5 h | EC to 154Gd; β– to 154Dy | 0 | 0.9 |
| 155Tb | 154.92350 | 5.3 d | EC to 155Gd | 3/2 | 2.0 |
| 156Tb | 155.924744 | 5.3 d | EC to 156Gd; β– to 156Dy | 3 | 1.4 |
| 157Tb | 156.924021 | 110 y | EC to 157Gd | 3/2 | 2.0 |
| 158Tb | 157.925410 | 180 y | EC to 158Gd; β– to 158Dy | 3 | 1.76 |
| 160Tb | 159.927164 | 72.3 d | β– to 160Dy | 3 | 1.79 |
| 161Tb | 160.927566 | 6.91 d | β– to 161Dy | 3/2 | 2.2 |