Element 103
Lawrencium
Actinides
Lawrencium (Lr) is in the d-block of the periodic table — group 3, period 7.
Lawrencium is a synthetic chemical element with chemical symbol Lr (formerly Lw) and atomic number 103.
Key data
- Atomic number
- 103
- Atomic mass
- 266.000 u
- Group / Period
- 3 / 7
- Block
- d-block
- Phase at STP
- Solid
- Density
- —
- Melting point
- 1626.8 °C
- Boiling point
- —
- Electron configuration
- [Rn] 5f14 7s2 7p1
Periodic table block
Lawrencium is in the d-block (group 3, period 7). Elements land in the d-block when their highest-energy electrons fill a d subshell — these are the transition metals in the middle of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Research only
- •Last actinide
- •Synthesized in 1961
Discovery
Year: 1961
Discovered by: Lawrence Berkeley National Laboratory
Frequently asked questions
What is the atomic number of Lawrencium?
Lawrencium has atomic number 103. Its symbol is Lr and its atomic mass is 266 u.
What category of element is Lawrencium?
Lawrencium is classified as actinides. It sits in group 3, period 7 of the periodic table.
What block of the periodic table is Lawrencium in?
Lawrencium is in the d-block (group 3, period 7). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, [Rn] 5f14 7s2 7p1.
What is Lawrencium used for?
Common uses of Lawrencium include: Research only, Last actinide, Synthesized in 1961.
When was Lawrencium discovered?
Lawrencium was discovered in 1961 by Lawrence Berkeley National Laboratory.
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