Lawrencium is the 103rd element in the Periodic Table. It is named after Ernest O. Lawrence who invented the cyclotron, a type of particle accelerator.

Symbol: Lr
Atomic Number: 103
Atomic Mass: 260.1054
No. of electrons/protons: 103
No. of neutrons: 259
Oxidation State: +3
Electron Configuration: 2,8,18,32,32,9,2

(Although Lawrencium's atomic mass is uncertain, it is generally accepted as 260.1054.)

Lawrencium was first created in March 1961 by four American scientists, Albert Ghiorso, Torbjorn Sikkeland, Almon E. Larsh and Robert M. Latimer. Placing 3 micrograms of californium in a linear particle accelerator, they bombarded it with some boron ions. This created an isotope of Lawrencium with a half-life of 8 seconds.

Since then other isotopes of Lawrencium have been created, the most stable one of which is lawrencium-262, with a half-life of 3.6 hours. It decays into nobelium through electron capture or spontaneous fission.