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Atomic Number	88

Atomic Symbol	Ra

Atomic Weight	[226 amu]

Group	Alkaline Earth, 2

Form	Solid

Density @ STP	5 g/cm³

Melting Point	700 °C (1292 °F, 973.15 °K)

Boiling Point	1736.85 °C (3158.33 °F, 2010 °K)

Heat of Fusion	8 kJ/mol (approx.)

Heat of Vaporization	125 kJ/mol (approx.)

First Ionization Potential	5.27892 eV

Electronegativity (on Pauling scale	0.9

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

Oxidation State(s)	+2

Selected Radioisotopes	²²³Ra, ²²⁴Ra, ²²⁶Ra, ²²⁸Ra

Crystal Structure	Cubic

Discovered by	Pierre and Marie Curie, 1898