Thulium

Lanthanide

Symbol: Tm

Atomic Number: 69

Standard State: Solid

Atomic Mass: 168.9342

Electron Configuration: [Xe]6s2 4f13

Electronegativity: 1.25

Atomic Radius: 227

Ionization Energy: 6.184

Melting Point: 1818

Boiling Point: 2223

Density: 9.32

Year Discovered: 1879