Symbol: Si
Atomic Number: 14
Atomic Weight: 28.0855
Element Classification: Semimetallic
Discovered By: Jons Jacob Berzelius
Discovery Date: 1824 (Sweden)
Name Origin: Latin: silex, silicus, (flint).
Density (g/cc): 2.33
Melting Point (K): 1683
Boiling Point (K): 2628
Appearance: Amorphous form is brown powder; crystalline form has a gray
Atomic Radius (pm): 132
Atomic Volume (cc/mol): 12.1
Covalent Radius (pm): 111
Ionic Radius: 42 (+4e) 271 (-4e)
Specific Heat (@20°C J/g mol): 0.703
Fusion Heat (kJ/mol): 50.6
Evaporation Heat (kJ/mol): 383
Thermal Conductivity (@25°C W/m K):
Debye Temperature (K): 625.00
Pauling Negativity Number: 1.90
First Ionizing Energy (kJ/mol): 786.0
Oxidation States: 4, -4
Electronic Configuration: [Ne] 3s² 3p²
Lattice Structure: Diagonal (DIA)
Lattice Constant (Å): 5.430
Lattice C/A Ratio: n/a