Seelicon

Seelicon, a tetravalent metalloid, is a chemical element wi the seembol Si an atomic nummer 14. It is less reactive nor its chemical analog caurbon, the nonmetal directly abuin it in the periodic table, but mair reactive nor germanium, the metalloid directly ablo it in the table. Controversy aboot seelicon's chairacter dates tae its discovery; it wis first prepared an characterized in pure furm in 1823. In 1808, it wis gien the name silicium (frae Laitin: silex, haird stane or flint), wi an -ium wird-endin tae suggest a metal, a name which the element retains in several non-Inglis leids. Houiver, its final Inglis name, first suggestit in 1817, reflects the mair pheesically seemilar elements carbon an boron.

Silicon, ₁₄Si

Silicon
Pronunciation	/ˈsɪlɪkən/ ​(SIL-ik-ən)
Appearance	crystalline, reflective wi bluish-tinged faces
Standard atomic weight Ar, std(Si)	[7001280840000000000♠28.084, 7001280860000000000♠28.086] conventional: 7001280850000000000♠28.085
Silicon in the periodic cairt
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Airn Cobalt Nickel Capper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Siller (element) Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gowd Mercur (element) Thallium Leid (element) Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium C ↑ Si ↓ Ge aluminium ← silicon → phosphorus
Atomic nummer (Z)	14
Group	group 14 (caurbon group)
Period	period 3
Block	p-block
Element category	Metalloid
Electron confeeguration	[Ne] 3s2 3p2
Electrons per shell	2, 8, 4
Pheesical properties
Phase at STP	solit
Meltin pynt	1687 K ​(1414 °C, ​2577 °F)
Bylin pynt	3538 K ​(3265 °C, ​5909 °F)
Density (near r.t.)	2.3290 g/cm3
when liquid (at m.p.)	2.57 g/cm3
Heat o fusion	50.21 kJ/mol
Heat o vapourisation	359 kJ/mol
Molar heat capacity	19.789 J/(mol·K)
Vapour pressur P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1908 2102 2339 2636 3021 3537
Atomic properties
Oxidation states	−4, −3, −2, −1, 0, +1, +2, +3, +4 (an amphoteric oxide)
Electronegativity	Pauling scale: 1.90
Ionisation energies	(more)
Atomic radius	empirical: 111 pm
Covalent radius	111 pm
Van der Waals radius	210 pm
Colour lines in a spectral range Spectral lines o silicon
Ither properties
Naitural occurrence	primordial
Creestal structur	​diamond cubic
Speed o soond thin rod	8433 m/s (at 20 °C)
Thermal expansion	2.6 µm/(m·K) (at 25 °C)
Thermal conductivity	149 W/(m·K)
Electrical resistivity	103 Ω·m (at 20 °C)
Magnetic orderin	diamagnetic
Young's modulus	130-188 GPa
Shear modulus	51-80 GPa
Bulk modulus	97.6 GPa
Poisson ratio	0.064 - 0.28
Mohs haurdness	7
CAS Nummer	7440-21-3
History
Prediction	Antoine Lavoisier (1787)
Diskivery	Jöns Jacob Berzelius (1823)
First isolation	Jöns Jacob Berzelius (1823)
Named by	Thomas Thomson (1817)
Main isotopes o silicon
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct 28Si 92.23% stable 29Si 4.67% stable 30Si 3.1% stable 32Si trace 153 y β− 32P