Yes. Lutetium is a metal, classified as a lanthanide on the periodic table.

How many protons does lutetium have?

Lutetium has 71 protons. Its atomic number is 71, which is also the number of electrons in a neutral atom of lutetium.

What group and period is lutetium in?

Lutetium is in period 6 of the periodic table. As a lanthanide in the d-block, it sits in a separate row below the main table and has no standard group number.

What is the atomic mass of lutetium?

The atomic mass of lutetium is 174.97 u (unified atomic mass units).

Element 71

Lutetium (Lu)

Lanthanide · Period 6 · d-block

Lutetium (Lu) is element 71 of the periodic table, a lanthanide in period 6 (d-block) with an atomic mass of 174.97 and is a solid at standard conditions.

At a glance

Atomic number: 71
Symbol: Lu
Atomic mass: 174.97 u
Category: Lanthanides
Period: 6
Block: d-block
Phase at STP: solid

Electron structure

Electron configuration: 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d1 6s2
Shorthand configuration: [Xe] 4f14 5d1 6s2
Electrons per shell: 2, 8, 18, 32, 9, 2
Oxidation states: +3

Physical properties

Melting point: 1,925 K (1,651.85 °C)
Boiling point: 3,675 K (3,401.85 °C)
Density: 9.84 g/cm³
Phase: solid

Atomic properties

Electronegativity (Pauling): 1.27
Atomic radius: 217 pm
Covalent radius: 187 pm
First ionization energy: 524 kJ/mol
Electron affinity: 50 kJ/mol

Notable isotopes

Notable isotopes of Lutetium: mass number, atomic mass, natural abundance, and stability.
Isotope	Mass	Abundance	Stability
Lu-175	174.94078	97.41%	Stable

Common uses

PET scanners
Catalysts
LED light bulbs
Dating meteorites

Discovery

Year: 1907
Discovered by: Georges Urbain, Carl Auer von Welsbach
Country: France/Austria

Frequently asked questions

Is lutetium a metal?: Yes. Lutetium is a metal, classified as a lanthanide on the periodic table.
How many protons does lutetium have?: Lutetium has 71 protons. Its atomic number is 71, which is also the number of electrons in a neutral atom of lutetium.
What group and period is lutetium in?: Lutetium is in period 6 of the periodic table. As a lanthanide in the d-block, it sits in a separate row below the main table and has no standard group number.
What is the atomic mass of lutetium?: The atomic mass of lutetium is 174.97 u (unified atomic mass units).

Keep exploring

Lutetium's row is on the printable element property sheet, and its tile is on the periodic table wall chart - the same numbers as above, laid out for A4 or A3 paper.