Lutetium
Lutetium is a chemical element with symbol Lu and atomic number 71. It is a silvery white metal, which resists corrosion in dry, but not in moist air. It is considered the first element of the 6th-period transition metals and the last element in the lanthanide series, and is traditionally counted among the rare earths.
A stylized shell model. Electrons are quantum objects, not particles following these literal paths. Sizes and motion are illustrative.
54 is the [Xe] core total across five shells.
At a glance
- Atomic number
- 71
- Atomic mass
- 174.96681 u
- Phase
- Solid
- Density
- 9.841 g/cm³
- Melting point
- 1,925 K
- Boiling point
- 3,675 K
- First ionization energy
- 523.5 kJ/mol
- Electronegativity
- 1.27
- Electron affinity
- 33.4 kJ/mol
- Molar heat capacity
- 26.86 J/(mol·K)
- Period
- 6
- Appearance
- silvery white
Conditions and isotopes affect measured properties. Some properties of short-lived elements are predicted. Electronegativity uses the Pauling scale.
Keep exploring
Explore the stories, imagery, and reference data in more depth. Properties with no value in the reference are marked unavailable.