Lutetium (Lu)

Lutetium is a chemical element with symbol Lu and atomic number 71. It is a silvery white metal, which resists corrosion in dry air, but not in moist air.

Atomic Number

71

Atomic Mass

174.97 u

Category

lanthanide

Phase

solid

Density

9.84 g/cm³

Electron Shells

2, 8, 18, 32, 9, 2

Atomic Structure

Protons: 71 • Electrons: 71 • Neutrons: Varies by isotope

Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹

Discovery

1907 • Georges Urbain, Carl Auer von Welsbach