103LrLawrencium266[Rn] 5f¹⁴ 7s² 7p¹
actinide

Lawrencium

Lawrencium is a synthetic chemical element with chemical symbol Lr (formerly Lw) and atomic number 103. It is named in honor of Ernest Lawrence, inventor of the cyclotron, a device that was used to discover many artificial radioactive elements. A radioactive metal, lawrencium is the eleventh transuranic element and is also the final member of the actinide series.

Electronic structure

A stylized shell model. Electrons are quantum objects, not particles following these literal paths. Sizes and motion are illustrative.

Electrons by shell
Electron configuration
5f14
7s2
7p1

86 is the [Rn] core total across six shells.

Properties

At a glance

Atomic number
103
Atomic mass
266 u
Phase
Solid
Density
Unavailable
Melting point
1,900 K
Boiling point
Unavailable
First ionization energy
470 kJ/mol
Electronegativity
1.3
Electron affinity
-30.04 kJ/mol
Molar heat capacity
Unavailable
Period
7
Appearance
Unavailable

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.