69Tm
Element 69
Thulium
Lanthanides
Thulium is a chemical element with symbol Tm and atomic number 69.
Key data
- Atomic number
- 69
- Atomic mass
- 168.934 u
- Group / Period
- 3 / 6
- Block
- f-block
- Phase at STP
- Solid
- Density
- 9.32 g/cm³
- Melting point
- 1544.8 °C
- Boiling point
- 1949.8 °C
- Electron configuration
- [Xe] 4f13 6s2
Common uses
- •Portable X-ray sources
- •Lasers
- •Glassmaking
Discovery
Year: 1879
Discovered by: Per Teodor Cleve
Frequently asked questions
What is the atomic number of Thulium?
Thulium has atomic number 69. Its symbol is Tm and its atomic mass is 168.934 u.
What category of element is Thulium?
Thulium is classified as lanthanides. It sits in group 3, period 6 of the periodic table.
What is Thulium used for?
Common uses of Thulium include: Portable X-ray sources, Lasers, Glassmaking.
When was Thulium discovered?
Thulium was discovered in 1879 by Per Teodor Cleve.
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