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103Lr

Element 103

Lawrencium

Actinides

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

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 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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