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Atomic Number	5

Atomic Symbol	B

Atomic Weight	10.811 amu

Group	Metalloid, 13

Form	Solid

Density @ STP	2.34 g/cm³

Melting Point	2075 °C (3767 °F, 2348.2 °K)

Boiling Point	4000 °C (7230 °F, 4273 °K)

Heat of Fusion	50.2 kJ/mol

Heat of Vaporization	480 kJ/mol

First Ionization Potential	8.29803 eV

Electronegativity (on Pauling scale	2.04

Specific Heat Capacity	1.026 J/g K

Ground State Electron Configuration	2p¹

Oxidation State(s)	+3

Stable Isotopes and Natural Abundance on Earth	¹⁰B, 19.9%; ¹¹B, 80.1%

Atomic Radius	87 pm

Crystal Structure	Rhombohedral

Discovered by	Davy; Gay-Lussac and Thenaerd; 1808 ;