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Name: Boron Symbol: B
Group: Non-Metal Atomic weight: 10.81
Density @ 293 K: 2.34 g/cm3 Atomic volume: 4.6 cm3/mol
Group: Non-Metal discovered: 1808


state (s, l, g): s
melting point: 2352.2 K boiling point: 3923.2 K
Heat of fusion: 50.20 kJ/mol Heat of vaporization: 489.70 kJ/mol


1st ionization energy: 800.6 kJ/mole
electronegativity: 2.04 2nd ionization energy: 2427 kJ/mole
electron affinity: 26.7 kJ/mole 3rd ionization energy: 3659.7 kJ/mole
Specific heat: 1.02 J/gK heat atomization: 573 kJ/mole atoms

Oxidation & Electrons:

Shells: 2,3 electron configuration: [He] 2s2 2p1
minimum oxidation number: 0 maximum oxidation number: 3
min. common oxidation no.: 0 max. common oxidation no.: 3

Appearance & Characteristics:

structure: special: B12 icosahedra color: black
uses: borax, glass making(B2O3) toxicity:
hardness: 9.5 mohs characteristics: B12 icosahedra; 3 forms


reaction with air: mild, w/ht =>B2O3
reaction with 6M HCl: none reaction with 6M HCl: none
reaction with 15M HNO3: none reaction with 6M NaOH: none

Other Forms:

number of isotopes: 2 hydride(s): B2H6 and many BxHy
oxide(s): B2O3 chloride(s): BCl3 and many BxCly


ionic radius (2- ion): pm ionic radius (1- ion): pm
atomic radius: 85 pm ionic radius (1+ ion): pm
ionic radius (2+ ion): pm ionic radius (3+ ion): 41 pm


thermal conductivity: 27.4 J/m-sec-deg
electrical conductivity: 0 1/mohm-cm polarizability: 3 A^3


source: Na and Ca borates (misc)
rel. abund. solar system: 1.326 log abundance earth's crust: 1 log
cost, pure: 250 $/100g cost, bulk: $/100g