69 Tm 168.934222

Thulium

LANTHANIDE

Phase: Solid

Discovered: Per Teodor Cleve

Block: F

Summary

Thulium is a chemical element with symbol Tm and atomic number 69. It is the thirteenth and antepenultimate (third-last) element in the lanthanide series. Like the other lanthanides, the most common oxidation state is +3, seen in its oxide, halides and other compounds.

Appearance: silvery gray

Source: Wikipedia

Physical Properties

Atomic Mass 168.934222 u

Density 9.32 g/cm³

Melting Point 1818 K

Boiling Point 2223 K

Molar Heat 27.03 J/(mol·K)

Electron Affinity 99 kJ/mol

Ionization Energies

1^st: 596.7 kJ/mol

2^nd: 1160 kJ/mol

3^rd: 2285 kJ/mol

4^th: 4120 kJ/mol