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Atomic Number	90

Atomic Symbol	Th

Atomic Weight	232.0381 amu

Group	Rare Earth (Actinide Series)

Form	Solid

Density @ STP	11.7 g/cm³

Melting Point	1750 °C (3182 °F, 2023.15 °K)

Boiling Point	4788 °C (8650.4 °F, 5061.15 °K)

Heat of Fusion	13.81 kJ/mol

Heat of Vaporization	530 kJ/mol

First Ionization Potential	6.08 eV

Electronegativity (on Pauling scale	1.3

Specific Heat Capacity	0.113 J/g K

Ground State Electron Configuration	5d¹⁰ 6s² 6p⁶ 6d² 6f²

Oxidation State(s)	+4

Stable Isotopes and Natural Abundance on Earth	²³²Th, 100%

Selected Radioisotopes	²²⁸Th, ²²⁹Th, ²³⁰Th, ²³²Th

Crystal Structure	Cubic

Discovered by	Berzelius, 1828