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Element 14 - Silicon (Si) sound

From silex. or flint; discovered 1823; the second most abundant element--making up one-quarter of the earth's crust. Sand, largely silicon dioxide, goes into making glass and cement. Pure silicon is used in micro-electronic devices such as solar batteries to power satellite instruments.

Properties

Atomic Number: 14
Atomic Weight: 28.0855
Electron Configuration (at ground state): 1s22s22p63s23p2
Oxidation States (Bold most stable): -4, +2, +4
Boiling Point (K): 2630
Melting Point (K): 1683
Density (at 300K -- g/cm3): 2.33
Atomic Volume (at 300K -- cm3/mol) 12.1
Number of stable isotopes: 3
Covalent Radius (Å): 1.11
Atomic Radius (Å): 1.32
First Ionization Potential (V): 8.151
Electronegativity (Pauling's): 1.90
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.70
Heat of Vaporization (kJ/mol): 359
Heat of Fusion (kJ/mol): 50.2
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 4 x 10-4
Thermal Conductivity (at 300K -- W m-1 K-1): 148
Crystal Structure: Cubic, face centered
Acid-Base Properties: Amphoteric