Atomic Number (# of protons)

65

Mass (amu)

158.9

Density

8.23 g/cm³ (20⁰C, 1 atm)

Electron Configuration

[Xe]4f⁹6s²

Oxidation States (bold = most stable)

+3,+4

Atomic Radius (pm)

176

Ionic Radius (pm)

(+3)118

Electronegativity

1.1

Melting Point (⁰C, 1 atm)

1356

Electron Affinity (eV)

Not Available

Boiling Point(⁰C, 1 atm)

3230

1^st Ionization energy (eV)

5.86

Enthalpy of Fusion (kJ/mole)

10.8

2^nd Ionization Energy (eV)

Enthalpy of Vaporization (kJ/mole)

330.9

3^rd Ionization Energy (eV)

Specific Heat Capacity ( J/ (g K), 25⁰C, 1 atm)

0.18