Our Elements
Menu

Lawrencium

Element 103 · Actinide

Specimen

Atomic number
103
Atomic mass
[266]
State at room temperature
Solid
Melting point
1,627 °C
Boiling point
Unknown
Density
Unknown
Discovered
1961

Mass number of the longest-lived isotope, from IUPAC.1 Other physical data from PubChem.2

Can I eat it?

In food and water
Never made in amounts you could eat. Laboratories make lawrencium a few atoms at a time, from californium hit with boron. Only a few atoms have ever existed. 3

See every element.

The atom

Lr
ShellElectrons
1 (K) 2
2 (L) 8
3 (M) 18
4 (N) 32
5 (O) 32
6 (P) 9
7 (Q) outermost 2
Total103

Configuration [Rn] 5f¹⁴ 6d¹ 7s²

5f ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓
6d ↑
7s ↑ ↓
A shell diagram: each ring is an electron shell and each dot is one electron. The nucleus holds 103 protons. The outermost shell is shown in red. Electrons do not travel on rings: they fill orbitals, regions where an electron is likely to be found. The boxes are those orbitals for the electrons outside the Rn core, with one arrow per electron. For lawrencium, some measurements are consistent with 7p¹ in place of 6d¹.

Related elements

Group 3
Sc Scandium Y Yttrium Lu Lutetium

New elements by e-mail

Sources

  1. 1

    IUPAC Commission on Isotopic Abundances and Atomic Weights (CIAAW), 2024. Radioactive Elements .

    Mass number and half-life of the longest-lived isotope of the 34 elements with no standard atomic weight.

  2. 2

    National Center for Biotechnology Information (PubChem), 2026. Periodic Table of Elements .

    Electron configuration, melting and boiling points, density and discovery year for all 118 elements.

  3. 3

    Royal Society of Chemistry, Periodic Table, 2026. Lawrencium - Element information, properties and uses .

    Reference page; its Biological role and Natural abundance sections are quoted.

    • Lawrencium has no known biological role. ... A radioactive metal of which only a few atoms have ever been created. ... It is produced by bombarding californium with boron.