Periodic TableAll elementsLutetium
No. 071
Lu
174.97 u
Element · Lanthanide

Lutetium

Lutetium (镥, symbol Lu) is chemical element number 71, a Lanthanide in period 6 of the periodic table, with a standard atomic weight of about 174.97. Hardest and densest of lanthanides. Used in petroleum cracking catalysts.

Period 6Group —[Xe] 4f¹⁴ 5d¹ 6s²

Properties

Atomic number71
SymbolLu
Atomic mass174.97 u
CategoryLanthanide
Period6
Group
Electron configuration[Xe] 4f¹⁴ 5d¹ 6s²
Electronegativity1.27
Covalent radius187 pm
Density9.84 g/cm³
Melting point1925 K
Boiling point3675 K
DiscoveryUrbain, von Welsbach, James, 1907

Overview

Hardest and densest of lanthanides. Used in petroleum cracking catalysts. Lutetium (Lu) holds position 71 in the periodic table, a Lanthanide in period 6. As a lanthanide (rare-earth) element it closely resembles its neighbours and serves in magnets, phosphors and catalysts.

Its electron configuration is [Xe] 4f¹⁴ 5d¹ 6s², with 2 electrons in the outer shell, and an electronegativity of about 1.27 (Pauling). Around 25 °C it is usually a solid; it melts near 1925 K (1651.9 °C), boils near 3675 K (3401.9 °C), has a density around 9.84 g/cm³.

In industry and daily life it turns up in Catalysis, Medical / Pharma and Research. It was first described by Urbain, von Welsbach, James in 1907.

Electron shells

Lu71

Electrons per shell: 2 · 8 · 18 · 32 · 9 · 2

Main uses

Hazard

LowNo special hazard flags.

Compounds containing Lutetium

No compounds in this knowledge base contain Lutetium yet.

Data sources

Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.