Thulium
Thulium (Tm)
Thulium is a chemical element with the symbol Tm and atomic number 69. It belongs to the lanthanide group and is a rare, silvery-white metal. Thulium was discovered in 1879 by Swedish chemist Per Teodor Cleve and named after Thule, a mythical island in the north.
Properties of Thulium
- Atomic Number: 69
- Symbol: Tm
- Atomic Mass: 168.93421 u
- Group: Lanthanides
- State at Room Temperature: Solid
- Density: 9.32 g/cm³
- Melting Point: 1545 °C
- Boiling Point: 1950 °C
Discovery and History
Thulium was discovered in 1879 by Swedish chemist Per Teodor Cleve while examining impurities in erbium oxide. He isolated the new element and named it after Thule, a legendary island from Greek and Roman mythology.
Applications and Uses
- Medical Lasers: Thulium-doped lasers are used in medical imaging and surgical procedures.
- X-ray Sources: Thulium-170 is used as a source for portable X-ray devices.
- Phosphors: Used in phosphors for color television tubes and fluorescent lamps.
- Research: Employed in various scientific experiments and investigations.
Safety Measures
Thulium and its compounds are considered moderately toxic. Protective measures should be taken to avoid direct contact and inhalation of dust.
Additional Information
More information about thulium and its applications can be found on scientific websites and in specialized literature.
Conclusion
Thulium is a versatile element with important applications in medicine, electronics, and research. Its unique properties make it a valuable material for various industrial and technological uses.