Atomic Number (# of protons)

78

Mass (amu)

195.1

Density

21.5 g/cm³ (20⁰C, 1 atm)

Electron Configuration

[Xe]4f¹⁴5d⁹6s¹

Oxidation States (bold = most stable)

+2,+4

Atomic Radius (pm)

139

Ionic Radius (pm)

(+4)63

Electronegativity

1.4

Melting Point (⁰C, 1 atm)

1769

Electron Affinity (eV)

2.13

Boiling Point(⁰C, 1 atm)

3827

1^st Ionization energy (eV)

9.0

Enthalpy of Fusion (kJ/mole)

19.7

2^nd Ionization Energy (eV)

Enthalpy of Vaporization (kJ/mole)

510.5

3^rd Ionization Energy (eV)

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

0.13