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103Lr266.000
Lawrencium
ActinideLawrencium is a synthetic chemical element with chemical symbol Lr (formerly Lw) and atomic number 103. It is named in honor of Ernest Lawrence, inventor of the cyclotron, a device that was used to discover many artificial radioactive elements. A radioactive metal, lawrencium is the eleventh transuranic element and is also the final member of the actinide series.
Phase: Solid
2, 8, 18, 32, 32, 8, 3
Physical Properties
Atomic Mass266 u
Melting Point1900 K
Period7
PhaseSolid
Chemical Properties
Electron Configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 7p1
Semantic Config[Rn] 5f14 7s2 7p1
Shells2, 8, 18, 32, 32, 8, 3
Electron Affinity-30.04 kJ/mol
Electronegativity1.3
Ionization Energies
IE1: 470 kJ/mol
Discovery
Discovered byLawrence Berkeley National Laboratory