Silicon

  • silicon, 14si
    siliconcroda.jpg
    silicon
    pronunciation
    • ən/
      (sil-ə-kən)
    • n/
      (sil-ə-kahn)
    appearancecrystalline, reflective with bluish-tinged faces
    standard atomic weight ar, std(si)[28.08428.086] conventional: 28.085
    silicon in the periodic table
    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
    aluminiumsiliconphosphorus
    atomic number (z)14
    groupgroup 14 (carbon group)
    periodperiod 3
    blockp-block
    element category  metalloid
    electron configuration[ne] 3s2 3p2
    electrons per shell2, 8, 4
    physical properties
    phase at stpsolid
    melting point1687 k ​(1414 °c, ​2577 °f)
    boiling point3538 k ​(3265 °c, ​5909 °f)
    density (near r.t.)2.3290 g/cm3
    when liquid (at m.p.)2.57 g/cm3
    heat of fusion50.21 kj/mol
    heat of vaporization383 kj/mol
    molar heat capacity19.789 j/(mol·k)
    vapor 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] +1,[2] +2, +3, +4 (an amphoteric oxide)
    electronegativitypauling scale: 1.90
    ionization energies
    • 1st: 786.5 kj/mol
    • 2nd: 1577.1 kj/mol
    • 3rd: 3231.6 kj/mol
    • (more)
    atomic radiusempirical: 111 pm
    covalent radius111 pm
    van der waals radius210 pm
    color lines in a spectral range
    spectral lines of silicon
    other properties
    natural occurrenceprimordial
    crystal structureface-centered diamond-cubic
    diamond cubic crystal structure for silicon
    speed of sound thin rod8433 m/s (at 20 °c)
    thermal expansion2.6 µm/(m·k) (at 25 °c)
    thermal conductivity149 w/(m·k)
    electrical resistivity2.3×103 Ω·m (at 20 °c)[3]
    band gap1.12 ev (at 300 k)
    magnetic orderingdiamagnetic[4]
    magnetic susceptibility−3.9·10−6 cm3/mol (298 k)[5]
    young's modulus130–188 gpa[6]
    shear modulus51–80 gpa[6]
    bulk modulus97.6 gpa[6]
    poisson ratio0.064–0.28[6]
    mohs hardness6.5
    cas number7440-21-3
    history
    namingafter latin 'silex' or 'silicis', meaning flint
    predictionantoine lavoisier (1787)
    discovery and first isolationjöns jacob berzelius[7][8] (1823)
    named bythomas thomson (1817)
    main isotopes of silicon
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    28si 92.2% stable
    29si 4.7% stable
    30si 3.1% stable
    31si trace 2.62 h β 31p
    32si trace 153 y β 32p
    category category: silicon
    | references

    silicon is a chemical element with the symbol si and atomic number 14. it is a hard, brittle crystalline solid with a blue-grey metallic lustre, and is a tetravalent metalloid and semiconductor. it is a member of group 14 in the periodic table: carbon is above it; and germanium, tin, and lead are below it. it is relatively unreactive. because of its high chemical affinity for oxygen, it was not until 1823 that jöns jakob berzelius was first able to prepare it and characterize it in pure form. its melting and boiling points of 1414 °c and 3265 °c respectively are the second-highest among all the metalloids and nonmetals, being only surpassed by boron. silicon is the eighth most common element in the universe by mass, but very rarely occurs as the pure element in the earth's crust. it is most widely distributed in dusts, sands, planetoids, and planets as various forms of silicon dioxide (silica) or silicates. more than 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 often with little processing of the natural minerals. such use includes industrial construction with clays, silica sand, and stone. silicates are used in portland cement for mortar and stucco, and mixed with silica sand and gravel to make concrete for walkways, foundations, and roads. they are also used in whiteware ceramics such as porcelain, and in traditional quartz-based soda-lime glass and many other specialty glasses. silicon compounds such as silicon carbide are used as abrasives and components of high-strength ceramics. silicon is the basis of the widely used synthetic polymers called silicones.

    the late 20th century to early 21st century has been described as the silicon age (also known as the digital age or information age) due to elemental silicon having a large impact on the modern world economy. the relatively small portion of very highly purified elemental silicon used in semiconductor electronics (< 10%) is essential to the metal-oxide-silicon (mos) transistors and integrated circuit chips used in most modern technology (such as computers and cell phones, for example). the most widely used silicon device is the mosfet (metal-oxide-silicon field-effect transistor), which has been manufactured in larger numbers than any other device in history. free silicon is also used in the steel refining, aluminium-casting, and fine chemical industries (often to make fumed silica).

    silicon is an essential element in biology, although only traces are required by animals. however, various sea sponges and microorganisms, such as diatoms and radiolaria, secrete skeletal structures made of silica. silica is deposited in many plant tissues.[9]

  • history
  • characteristics
  • chemistry and compounds
  • occurrence
  • production
  • applications
  • biological role
  • safety
  • see also
  • references
  • bibliography
  • external links

Silicon, 14Si
SiliconCroda.jpg
Silicon
Pronunciation
Appearancecrystalline, reflective with bluish-tinged faces
Standard atomic weight Ar, std(Si)[28.08428.086] conventional: 28.085
Silicon in the periodic table
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
aluminiumsiliconphosphorus
Atomic number (Z)14
Groupgroup 14 (carbon group)
Periodperiod 3
Blockp-block
Element category  Metalloid
Electron configuration[Ne] 3s2 3p2
Electrons per shell2, 8, 4
Physical properties
Phase at STPsolid
Melting point1687 K ​(1414 °C, ​2577 °F)
Boiling point3538 K ​(3265 °C, ​5909 °F)
Density (near r.t.)2.3290 g/cm3
when liquid (at m.p.)2.57 g/cm3
Heat of fusion50.21 kJ/mol
Heat of vaporization383 kJ/mol
Molar heat capacity19.789 J/(mol·K)
Vapor 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] +1,[2] +2, +3, +4 (an amphoteric oxide)
ElectronegativityPauling scale: 1.90
Ionization energies
  • 1st: 786.5 kJ/mol
  • 2nd: 1577.1 kJ/mol
  • 3rd: 3231.6 kJ/mol
  • (more)
Atomic radiusempirical: 111 pm
Covalent radius111 pm
Van der Waals radius210 pm
Color lines in a spectral range
Spectral lines of silicon
Other properties
Natural occurrenceprimordial
Crystal structureface-centered diamond-cubic
Diamond cubic crystal structure for silicon
Speed of sound thin rod8433 m/s (at 20 °C)
Thermal expansion2.6 µm/(m·K) (at 25 °C)
Thermal conductivity149 W/(m·K)
Electrical resistivity2.3×103 Ω·m (at 20 °C)[3]
Band gap1.12 eV (at 300 K)
Magnetic orderingdiamagnetic[4]
Magnetic susceptibility−3.9·10−6 cm3/mol (298 K)[5]
Young's modulus130–188 GPa[6]
Shear modulus51–80 GPa[6]
Bulk modulus97.6 GPa[6]
Poisson ratio0.064–0.28[6]
Mohs hardness6.5
CAS Number7440-21-3
History
Namingafter Latin 'silex' or 'silicis', meaning flint
PredictionAntoine Lavoisier (1787)
Discovery and first isolationJöns Jacob Berzelius[7][8] (1823)
Named byThomas Thomson (1817)
Main isotopes of silicon
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
28Si 92.2% stable
29Si 4.7% stable
30Si 3.1% stable
31Si trace 2.62 h β 31P
32Si trace 153 y β 32P
Category Category: Silicon
| references

Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic lustre, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic table: carbon is above it; and germanium, tin, and lead are below it. It is relatively unreactive. Because of its high chemical affinity for oxygen, it was not until 1823 that Jöns Jakob Berzelius was first able to prepare it and characterize it in pure form. Its melting and boiling points of 1414 °C and 3265 °C respectively are the second-highest among all the metalloids and nonmetals, being only surpassed by boron. Silicon is the eighth most common element in the universe by mass, but very rarely occurs as the pure element in the Earth's crust. It is most widely distributed in dusts, sands, planetoids, and planets as various forms of silicon dioxide (silica) or silicates. More than 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 often with little processing of the natural minerals. Such use includes industrial construction with clays, silica sand, and stone. Silicates are used in Portland cement for mortar and stucco, and mixed with silica sand and gravel to make concrete for walkways, foundations, and roads. They are also used in whiteware ceramics such as porcelain, and in traditional quartz-based soda-lime glass and many other specialty glasses. Silicon compounds such as silicon carbide are used as abrasives and components of high-strength ceramics. Silicon is the basis of the widely used synthetic polymers called silicones.

The late 20th century to early 21st century has been described as the Silicon Age (also known as the Digital Age or Information Age) due to elemental silicon having a large impact on the modern world economy. The relatively small portion of very highly purified elemental silicon used in semiconductor electronics (< 10%) is essential to the metal-oxide-silicon (MOS) transistors and integrated circuit chips used in most modern technology (such as computers and cell phones, for example). The most widely used silicon device is the MOSFET (metal-oxide-silicon field-effect transistor), which has been manufactured in larger numbers than any other device in history. Free silicon is also used in the steel refining, aluminium-casting, and fine chemical industries (often to make fumed silica).

Silicon is an essential element in biology, although only traces are required by animals. However, various sea sponges and microorganisms, such as diatoms and radiolaria, secrete skeletal structures made of silica. Silica is deposited in many plant tissues.[9]