Sílíkọ́nù

Sílíkọ́nù, a tetravalent metalloid, is a chemical element with the symbol Si and atomic number 14. It is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table. Controversy about silicon's character dates to its discovery: silicon was first prepared and characterized in pure form in 1823. In 1808, it was given the name silicium (from Látìnì: silicis, flints), with an -ium word-ending to suggest a metal, a name which the element retains in several non-English languages. However, its final English name, first suggested in 1817, reflects the more physically similar elements carbon and boron.

Sílíkọ́nù, ₁₄Si

Sílíkọ́nù
Pípè	/ˈsɪlᵻkən/ (SIL-ə-kən) /ˈsɪləkɒn/ (SIL-ə-kahn)
Ìhànsójú	crystalline, reflective with bluish-tinged faces
Ìwúwo átọ̀mù Ar, std(Si)	[28.084, 28.086] conventional: 28.085
Sílíkọ́nù ní orí tábìlì àyè
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 Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver 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 Gold Mercury (element) Thallium Lead 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 Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson C ↑ Si ↓ Ge aluminium ← sílíkọ́nù → phosphorus
Nọ́mbà átọ̀mù (Z)	14
Ẹgbẹ́	group 14 (carbon group)
Àyè	àyè 3
Àdìpọ̀	Àdìpọ̀-p
Ẹ̀ka ẹ́límẹ́ntì	Metalloid
Ìtò ẹ̀lẹ́ktrọ́nù	[Ne] 3s2 3p2
Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan	2, 8, 4
Àwọn ohun ìní ara
Ìfarahàn at STP	solid
Ìgbà ìyọ́	1687 K ​(1414 °C, ​2577 °F)
Ígbà ìhó	3538 K ​(3265 °C, ​5909 °F)
Kíki (near r.t.)	2.3290 g/cm3
when liquid (at m.p.)	2.57 g/cm3
Heat of fusion	50.21 kJ/mol
Heat of	359 kJ/mol
Molar heat capacity	19.789 J/(mol·K)
pressure 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 Àdàkọ:Infobox element/symbol-to-oxidation-state/comment
Electronegativity	Pauling scale: 1.90
energies	(more)
Atomic radius	empirical: 111 pm
Covalent radius	111 pm
Van der Waals radius	210 pm
Spectral lines of sílíkọ́nù
Other properties
Natural occurrence	primordial
Crystal structure	​
Speed of sound 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 ordering	diamagnetic
Young's modulus	130-188 GPa
Shear modulus	51-80 GPa
Bulk modulus	97.6 GPa
Poisson ratio	0.064 - 0.28
Mohs hardness	7
CAS Number	7440-21-3
History
Prediction	Antoine Lavoisier (1787)
Discovery	Jöns Jacob Berzelius (1824)
First isolation	Jöns Jacob Berzelius (1824)
Named by	Thomas Thomson (1831)
Main isotopes of sílíkọ́nù
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct 28Si 92.23% 28Si is stable with 14 neutrons 29Si 4.67% 29Si is stable with 15 neutrons 30Si 3.1% 30Si is stable with 16 neutrons 32Si trace 153 y β− 13.020 32P

Silicon is the eighth most common element in the universe by mass, but very rarely occurs as the pure free element in nature. It is most widely distributed in dusts, sands, planetoids, and planets as various forms of silicon dioxide (silica) or silicates. Over 90% of the Earth's crust is composed of silicate minerals, making silicon the second most abundant element in the Earth's crust (about 28% by mass) after oxygen.

Most silicon is used commercially without being separated, and indeed often with little processing of compounds from nature. These include direct industrial building-use of clays, silica sand and stone. Silica is used in ceramic brick. Silicate goes into Portland cement for mortar and stucco, and when combined with silica sand and gravel, to make concrete. Silicates are also in whiteware ceramics such as porcelain, and in traditional quartz-based soda-lime glass. More modern silicon compounds such as silicon carbide form abrasives and high-strength ceramics. Silicon is the basis of the ubiquitous synthetic silicon-based polymers called silicones.

Elemental silicon also has a large impact on the modern world economy. Although most free silicon is used in the steel refining, aluminum-casting, and fine chemical industries (often to make fumed silica), the relatively small portion of very highly purified silicon that is used in semiconductor electronics (< 10%) is perhaps even more critical. Because of wide use of silicon in integrated circuits, the basis of most computers, a great deal of modern technology depends on it.

Silicon is an essential element in biology, although only tiny traces of it appear to be required by animals, however various sea sponges as well as microorganisms like diatoms need silicon in order to have structure. It is much more important to the metabolism of plants, particularly many grasses.