69 · Tm
Thulium
Separated by Cleve in 1879.
Identity
- Atomic number
- 69
- Symbol
- Tm
- Canonical name
- Thulium
- Category
- lanthanide
- Group
- unassigned
- Period
- 6
- Block
- f
Series set apart from the main table. Whether group 3 is lanthanum or lutetium (actinium or lawrencium) is still discussed, so the group is left empty.
Properties
These quantities come from the Periodic Table JSON compilation. They have not yet been checked, one by one, against CIAAW atomic weights or NIST measurements. A value marked estimated is not a measurement.
- Atomic mass
- 168.934222 u
- Electron configuration
- [Xe] 4f13 6s2
- Electrons per shell
- 2, 8, 18, 31, 8, 2
- Standard state
- solid
- Density
- 9.32 g/cm³
- Melting point
- 1,818 K
- Boiling point
- 2,223 K
- Electronegativity
- 1.25 Pauling
- First ionization energy
- 596.7 kJ/mol
- Electron affinity
- 99 kJ/mol
Notable isotopes
This summary is not an inventory of every isotope.
- Tm-169 · 100 % · stable
History
Thulium
Discovery · confirmed · 1879
Cleve separates thulium from erbium earths.
Etymology
- Theme
- place
- Language
- grec
- Root
- Thule
- Meaning
- Thule, an old name for the far north
Scientists
Places and institutions
- Uppsala — historical setting : Sweden — present country : Sweden
See also
Sources
- IUPAC, Periodic Table of the Elements
- Bowserinator, Periodic Table JSON. Compilation secondaire d’où viennent les grandeurs physiques importées (masse, densité, températures, énergies). Elles ne sont pas revérifiées une à une auprès du NIST ou de la CIAAW.
- John Emsley, Nature’s Building Blocks: An A–Z Guide to the Elements