71 · Lu
Lutetium
Separated in 1907 by Urbain, von Welsbach, and James. The name kept is Urbain’s.
Identity
- Atomic number
- 71
- Symbol
- Lu
- Canonical name
- Lutetium
- Category
- lanthanide
- Group
- unassigned
- Period
- 6
- Block
- d
- Former names
- cassiopéium
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
- 174.96681 u
- Electron configuration
- [Xe] 4f14 5d1 6s2
- Electrons per shell
- 2, 8, 18, 32, 9, 2
- Standard state
- solid
- Density
- 9.841 g/cm³
- Melting point
- 1,925 K
- Boiling point
- 3,675 K
- Electronegativity
- 1.27 Pauling
- First ionization energy
- 523.5 kJ/mol
- Electron affinity
- 33.4 kJ/mol
History
Lutetium
Discovery · jointly credited · 1907
Urbain separates lutetium from ytterbium and proposes this name.
Cassiopeium
Discovery · jointly credited · 1907
Von Welsbach separates the same element and calls it cassiopeium. The name kept is lutetium.
Independent separation
Discovery · jointly credited · 1907
James also achieves the separation. Publication priority favors Urbain, without erasing the parallel work.
Etymology
- Theme
- place
- Language
- latin
- Root
- Lutetia
- Meaning
- Lutetia, Paris
Scientists
Places and institutions
- Paris — historical setting : France — present country : France
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