Atomic NumberAtomic Number of Thulium
Atomic Number of Thulium is 69.
Chemical symbol for Thulium is Tm. Number of protons in Thulium is 69. Atomic weight of Thulium is 168.93422 u or g/mol. Melting point of Thulium is 1545 °C and its the boiling point is 1727 °C.
» Boiling Point » Melting Point » Abundant » State at STP » Discovery YearAbout Thulium
Thulium is one of the lanthanides discovered by Swedish scientists and named after an old name for Scandinavia, Thule. It is a shiny metal of slivery color, which can be extracted from a number of minerals on our planet. Its properties are similar to the ones of other lanthanides. Thulium is not a toxic element and it has no importance for life. The main uses of this element include some lasers and X-ray machines for a variety of medical purposes.
Properties of Thulium Element
| Atomic Number (Z) | 69 |
|---|---|
| Atomic Symbol | Tm |
| Group | |
| Period | 6 |
| Atomic Weight | 168.93422 u |
| Density | 9.321 g/cm3 |
| Melting Point (K) | 1818 K |
| Melting Point (℃) | 1545 °C |
| Boiling Point (K) | 2223 K |
| Boiling Point (℃) | 1727 °C |
| Heat Capacity | 0.16 J/g · K |
| Abundance | 0.52 mg/kg |
| State at STP | Solid |
| Occurrence | Primordial |
| Description | Lanthanide |
| Electronegativity (Pauling) χ | 1.25 |
| Ionization Energy (eV) | 6.18431 |
| Atomic Radius | 175pm |
| Covalent Radius | no datapm |
| Valence Electrons | 2 |
| Year of Discovery | 1879 |
| Discoverer | Cleve |