Lr
Lawrencium
Element 103 · Actinide
Lawrencium (Lr)
Lawrencium is the last actinide, a synthetic element made by bombarding californium with boron ions.
- Actinide
- Period 7
- f-block series
- d-block
- solid at room temperature
- ☢ Radioactive
Key properties
- Atomic mass
- [266]
- u
- Electron configuration
- [Rn] 5f14 7s2 7p1
- Melting point
- 1,626.9 °C
- 1,900 K
- Boiling point
- —
- Density
- —
- Electronegativity
- 1.3
- Pauling
- Atomic radius
- —
- 1st ionisation energy
- —
Compare with every element:Electronegativity chartAtomic radius chartIonisation energy chartDensity chart of the elementsMelting point chartElectron configuration chart
Did you know?
Notable facts about lawrencium
- 01
Its symbol was originally Lw; it was changed to Lr in 1963.
- 02
Experiments suggest its outermost electron is in a p orbital, unusual for its group.
- 03
Whether it belongs in group 3 is still debated by chemists.
Applications
What is lawrencium used for?
- Research
History
Discovery & name origin
Discovered by
Albert Ghiorso, Torbjørn Sikkeland, Almon Larsh, Robert M. Latimer
Year
Where
United States
Name origin
From Ernest Lawrence, inventor of the cyclotron.
Atomic structure
Atomic properties
Atomic structure
Atomic properties
- Atomic number
- 103
- Atomic mass
- [266] u
- Group
- Actinides (3)
- Period
- 7
- Block
- d-block
- Electron configuration
- [Rn] 5f14 7s2 7p1
- Full configuration
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 7p1
- Electrons per shell
- 2, 8, 18, 32, 32, 8, 3
- Electronegativity (Pauling)
- 1.3
- Electron affinity
- —
- Atomic radius (van der Waals)
- —
- Stable isotopes
- None — all isotopes are radioactive
Oxidation states
Highlighted: common oxidation states (+3).
Physical
Physical properties & colour
Physical
Physical properties & colour
- State at 20 °C
- Solid
- Melting point
- 1,900 K · 1,626.9 °C · 2,960.3 °F
- Boiling point
- —
- Density
- —
- Molar heat capacity
- —
- Appearance
- —
- CPK model colour
- Copied
The CPK colour is the convention used for this element’s atoms in molecular models.
FAQ
Lawrencium questions
What is Lr on the periodic table?
Lr is the symbol for lawrencium, element 103 on the periodic table. It sits in period 7, in the f-block, in the actinide category, and has an atomic mass of [266].
What is the atomic number of lawrencium?
Lawrencium has atomic number 103, so every lawrencium atom has 103 protons in its nucleus. Its symbol is Lr and its atomic mass is [266].
Who discovered lawrencium?
Lawrencium was discovered by Albert Ghiorso, Torbjørn Sikkeland, Almon Larsh and Robert M. Latimer in 1961 (United States). The name comes from from Ernest Lawrence, inventor of the cyclotron.
What is lawrencium used for?
Lawrencium is used for: research.
Is lawrencium a metal?
Yes. Lawrencium is a actinide, one of the metallic elements.
What is the electron configuration of lawrencium?
The electron configuration of lawrencium is [Rn] 5f14 7s2 7p1. Its 103 electrons are arranged in shells as 2, 8, 18, 32, 32, 8, 3.