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Encyclopedia > Silex
14 aluminiumsiliconphosphorus
C

Si

Ge
General
Name, Symbol, Number silicon, Si, 14
Chemical series metalloids
Group, Period, Block 14, 3, p
Appearance dark gray, bluish tinge
Atomic mass 28.0855(3) g/mol
Electron configuration [Ne] 3s2 3p2
Electrons per shell 2, 8, 4
Physical properties
Phase solid
Density (near r.t.) 2.33 g/cm³
Liquid density at m.p. 2.57 g/cm³
Melting point 1687 K
(1414 °C, 2577 °F)
Boiling point 3538 K
(3265 °C, 5909 °F)
Heat of fusion 50.21 kJ/mol
Heat of vaporization 359 kJ/mol
Heat capacity (25 °C) 19.789 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
Crystal structure cubic face centered
Oxidation states 4
(amphoteric oxide)
Electronegativity 1.90 (Pauling scale)
Ionization energies
(more)
1st: 786.5 kJ/mol
2nd: 1577.1 kJ/mol
3rd: 3231.6 kJ/mol
Atomic radius 110 pm
Atomic radius (calc.) 111 pm
Covalent radius 111 pm
Van der Waals radius 210 pm
Miscellaneous
Magnetic ordering nonmagnetic
Thermal conductivity (300 K) 149 W/(m·K)
Thermal expansion (25 °C) 2.6 µm/(m·K)
Speed of sound (thin rod) (20 °C) 2200 m/s
Young's modulus 47 GPa
Bulk modulus 100 GPa
Mohs hardness 6.5
CAS registry number 7440-21-3
Notable isotopes
Main article: Isotopes of silicon
iso NA half-life DM DE (MeV) DP
28Si 92.23% Si is stable with 14 neutrons
29Si 4.67% Si is stable with 15 neutrons
30Si 3.1% Si is stable with 16 neutrons
32Si syn 132 y β- 0.221 32P
References

Silicon (Latin: silicium) is the chemical element in the periodic table that has the symbol Si and atomic number 14. A tetravalent metalloid, silicon is less reactive than its chemical analog carbon. It is the second most abundant element in the Earth's crust, making up 25.7% of it by weight. It occurs in clay, feldspar, granite, quartz and sand, mainly in the form of silicon dioxide (also known as silica) and silicates (compounds containing silicon, oxygen and metals). Silicon is the principal component of glass, cement, ceramics, most semiconductor devices, and silicones, the latter a plastic substance often confused with silicon. Silicon is widely used in semiconductors because the semiconductor Germanium has a problem with reverse leakage current flow, and because its native oxide forms better semiconductor/dielectric interfaces than almost all other material combinations. General Name, Symbol, Number aluminium, Al, 13 Chemical series poor metals Group, Period, Block 13, 3, p Appearance silvery Atomic mass 26. ... This article is about the chemical element. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... General Name, Symbol, Number germanium, Ge, 32 Chemical series metalloids Group, Period, Block 14, 4, p Appearance grayish white Atomic mass 72. ... Silicon table image created for Wikipedia by Schnee on June 24, 2003, 23:23 UTC. Licensed under the terms of the GNU FDL. File links The following pages link to this file: Silicon User:Femto/elements e2 Categories: GFDL images ... State at standard temperature and pressure those numbered in red are gases those numbered in green are liquids those numbered in black are solid Natural occurrence those without borders have not been discovered/synthesized yet those with dotted borders do not occur naturally (Synthetic elements) those with dashed borders naturally... This is a list of chemical elements, sorted by name and color coded according to type of element. ... Categories: Chemical elements ... A chemical series is a group of chemical elements whose physical and chemical characteristics vary progressively from one end of the series to another. ... Together with the metals and nonmetals, the metalloids (in Greek metallon = metal and eidos = sort - also called semimetals) form one of the three categories of chemical elements as classified by ionization and bonding properties. ... A periodic table group is a vertical column in the periodic table of the chemical elements. ... In the periodic table of the elements, a period is a row of the table. ... A block of the periodic table of elements is a set of adjacent groups. ... The carbon group is group 14 (IUPAC style) in the periodic table. ... A period 3 element is one of the chemical elements in the third row (or period) of the periodic table of the elements. ... The p-block of the periodic table of elements consists of the last six groups. ... Colour is an important part of the visual arts. ... Silicon sample. ... The atomic mass of an element (also known as the relative atomic mass or average atomic mass or atomic weight) is the average atomic mass of all the chemical elements isotopes as found in a particular environment, weighted by isotopic abundance. ... To help compare different orders of magnitude we list here masses between 6. ... Electron atomic and molecular orbitals In atomic physics, the electron configuration is the arrangement of electrons in an atom, molecule or other body. ... General Name, Symbol, Number neon, Ne, 10 Chemical series noble gases Group, Period, Block 18, 2, p Appearance colorless Atomic mass 20. ... Properties The electron is a fundamental subatomic particle which carries a negative electric charge. ... A quantum mechanic system can only be in certain states, so that only certain energy levels are possible. ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... A solid is a phase of matter, characterized by resistance to deformation and changes of volume. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... Room temperature, in laboratory reports, is taken to be roughly 21–23 degrees Celsius (70 degrees Fahrenheit), or 294–296 kelvins. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... The melting point of a solid is the temperature at which it changes state from solid to liquid. ... The melting point of a solid is the temperature at which it changes state from solid to liquid. ... The title of this article is incorrect due to technical limitations. ... The degree Celsius (°C or ℃ (Unicode 0x2103)) is a unit of temperature named after the Swedish astronomer Anders Celsius (1701–1744), who first proposed a similar system in 1742. ... Fahrenheit is a temperature scale named after the German physicist Gabriel Fahrenheit (1686–1736), who proposed it in 1724. ... The boiling point of a substance is the temperature at which it can change state from a liquid to a gas throughout the bulk of the liquid. ... The title of this article is incorrect due to technical limitations. ... The degree Celsius (°C or ℃ (Unicode 0x2103)) is a unit of temperature named after the Swedish astronomer Anders Celsius (1701–1744), who first proposed a similar system in 1742. ... Fahrenheit is a temperature scale named after the German physicist Gabriel Fahrenheit (1686–1736), who proposed it in 1724. ... Heat of fusion is the amount of heat energy which must be absorbed or lost for 1 gram of a substance to change states from a solid to a liquid or vice versa. ... Kilojoule per mole are an SI derived unit of energy per amount of material, where energy is measured in units of 1000 joules, and the amount of material is measured in mole units. ... The heat of vaporization is a physical property of substances. ... Kilojoule per mole are an SI derived unit of energy per amount of material, where energy is measured in units of 1000 joules, and the amount of material is measured in mole units. ... Heat capacity (abbreviated Cth or just C, also called thermal capacity) is the ability of matter to store heat. ... The vapor pressure is the pressure (if the vapor is mixed with other gases, the partial pressure) of a vapor. ... Rose des Sables (Sand Rose), formed of gypsum crystals In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. ... The oxidation state or oxidation number is defined as the sum of negative and positive charges in an atom, which indirectly indicates the number of electrons it has accepted or donated. ... In chemistry, an amphoteric substance is one that can react with either an acid or base (more generally, the word describes something made of, or acting like, two components). ... Electronegativity is the measure of the ability of an atom or molecule to attract electrons in the context of a chemical bond. ... Electronegativity is a measure of the attraction that an atom has for the bonding pair of electrons in a covalent bond. ... The ionization energy (IE) of an atom or of a molecule is the energy required to strip it of an electron. ... These tables list the ionization energy in kJ/mol necessary to remove an electron from a neutral atom (first energy), respectively from a singly, doubly, etc. ... Kilojoule per mole are an SI derived unit of energy per amount of material, where energy is measured in units of 1000 joules, and the amount of material is measured in mole units. ... The atomic radius is the distance from the atomic nucleus to the outmost stable electron orbital in a atom that is at equilibrium. ... To help compare different orders of magnitude this page lists lengths between 100 pm and 1 nm (10-10 m and 10-9 m). ... Picometre (American spelling: picometer) is an SI measure of length that is equal to 10−12 of a metre. ... The atomic radius is the distance from the atomic nucleus to the outmost stable electron orbital in a atom that is at equilibrium. ... To help compare different orders of magnitude this page lists lengths between 100 pm and 1 nm (10-10 m and 10-9 m). ... Picometre (American spelling: picometer) is an SI measure of length that is equal to 10−12 of a metre. ... Covalent radius in chemistry corresponds to half of the distance between two identical atomic nuclei, bound by a covalent bond. ... To help compare different orders of magnitude this page lists lengths between 100 pm and 1 nm (10-10 m and 10-9 m). ... Picometre (American spelling: picometer) is an SI measure of length that is equal to 10−12 of a metre. ... The van der Waals radius of an atom is the radius of an imaginary hard sphere which can be used to model the atom for many purposes. ... To help compare different orders of magnitude this page lists lengths between 100 pm and 1 nm (10-10 m and 10-9 m). ... Picometre (American spelling: picometer) is an SI measure of length that is equal to 10−12 of a metre. ... In physics, magnetism is one of the phenomena by which materials exert an attractive or repulsive force on other materials. ... In physics, thermal conductivity, λ, is the intensive property of a material which relates its ability to conduct heat. ... In physics, thermal conductivity, λ, is the quantity of heat transmitted, due to unit temperature gradient, in unit time under steady conditions in a direction normal to a surface of unit area, when the heat transfer is dependent only on the temperature gradient thermal conductivity = heat flow rate / (distance × temperature... The coefficient of thermal expansion is used in two ways: as a volumetric thermal expansion coefficient as a linear thermal expansion coefficient These characteristics are closely related. ... The speed of sound c (from Latin celeritas, velocity) varies depending on the medium through which the sound waves pass. ... Metre per second (U.S. spelling: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector), defined by distance in metres divided by time in seconds. ... In solid mechanics, Youngs modulus (also known as the modulus of elasticity or elastic modulus) is a measure of the stiffness of a given material. ... The bulk modulus K of a fluid or solid is the inverse of the compressibility: where p is pressure and V is volume. ... Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... Silicon (Si) Standard atomic mass: 28. ... Isotopes are forms of an element whose nuclei have the same atomic number–-the number of protons in the nucleus--but different atomic masses because they contain different numbers of neutrons. ... Natural abundance refers to the prevalence of different isotopes of an element as found in nature. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... In physics, the decay mode describes a particular way a particle decays. ... The decay energy is the energy released by a nuclear decay. ... An electronvolt (symbol: eV) is the amount of energy gained by a single unbound electron when it falls through an electrostatic potential difference of one volt. ... In nuclear physics, a decay product, also known as a daughter product, is a nuclide resulting from the radioactive decay of a parent or precursor nuclide. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... To help compare orders of magnitude of different times this page lists times between 109 seconds (a gigasecond) and 1010 seconds (32 years and 320 years). ... In nuclear physics, beta decay (sometimes called neutron decay) is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. ... This article is about the chemical element. ... Recommended values for many properties of the elements, together with various references, are collected on these data pages. ... A chemical element, often called simply element, is the class of atoms which contain the same number of protons. ... The periodic table of the chemical elements, also called the Mendeleev periodic table, is a tabular display of the known chemical elements. ... The atomic number (Z) is a term used in chemistry and physics to represent the number of protons found in the nucleus of an atom. ... In chemistry, a tetravalent atom in a molecule has 4 electrons available for chemical bonding in its outer valence shell. ... Together with the metals and nonmetals, the metalloids (in Greek metallon = metal and eidos = sort - also called semimetals) form one of the three categories of chemical elements as classified by ionization and bonding properties. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third-closest planet to the Sun. ... Clay is a generic term for an aggregate of hydrous silicate particles less than 4 μm (micrometres) in diameter. ... Feldspar is the name of an important group of rock-forming minerals which make up perhaps as much as 60% of the Earths crust. ... Quarrying granite for the Mormon Temple, Utah Territory. ... Quartz is the most abundant mineral in the Earths crust. ... Patterns in the sand Sand is an example of a class of materials called granular matter. ... The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ... In chemistry, a silicate is a compound consisting of silicon and oxygen (SixOy), one or more metals, and possibly hydrogen. ... The materials definition of a glass is a uniform amorphous solid material, usually produced when a suitably viscous molten material cools very rapidly, thereby not giving enough time for a regular crystal lattice to form. ... In the general sense, a cement (Latin caementum) is any material with adhesive properties. ... The word ceramic is derived from the Greek word Κεραμεικος (the name of a suburb of Athens), and in its strictest sense refers to clay in all its forms. ... Derka semiconductor is a material with an electrical conductance that is intermediate between that of an insulator and a conductor. ... Silicones, or polysiloxanes, are inorganic polymers consisting of a silicon-oxygen backbone (...-Si-O-Si-O-Si-O-...) with side groups attached to the silicon atoms. ... General Name, Symbol, Number germanium, Ge, 32 Chemical series metalloids Group, Period, Block 14, 4, p Appearance grayish white Atomic mass 72. ... Reverse leakage current in the semiconductor is the current flowing from the semiconductor when we reverse bias that device. ... Passivation is the process of making a material passive in relation to another material prior to using the materials together. ...

Contents


Notable characteristics

In its crystalline form, silicon has a dark gray color and a metallic luster. Even though it is a relatively inert element, silicon still reacts with halogens and dilute alkalis, but most acids (except for a combination of nitric acid and hydrofluoric acid) do not affect it. Elemental silicon transmits more than 95% of all wavelengths of infrared light. Pure silicon crystals are rarely found in nature, as natural silicon is usually found as silica (SiO2). Pure silicon crystals can be found as inclusions in gold, or in volcanic exhalations. Pure silicon has a negative temperature co-efficient of resistance, since the number of free charge carriers increases with temperature. Quartz crystal A crystal is a solid in which the constituent atoms, molecules, or ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions. ... For the halogen light bulb, click here. ... For the battery, see alkaline battery The word alkali can mean:- In chemistry, an alkali is a specific type of base, formed as a carbonate, hydroxide or other ionic salt of an alkali metal or alkali earth metal element. ... An acid (often represented by the generic formula AH) is typically a water-soluble, sour-tasting chemical compound. ... The chemical compound nitric acid (HNO3), otherwise known as aqua fortis, is a colorless, corrosive liquid, a toxic acid which can cause severe burns. ... Hydrofluoric acid is a highly corrosive solution of the chemical compound hydrogen fluoride in water. ... The wavelength is the distance between repeating units of a wave pattern. ... The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ... General Name, Symbol, Number gold, Au, 79 Chemical series transition metals Group, Period, Block 11, 6, d Appearance metallic yellow Atomic mass 196. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... Resistance can mean one of: electrical resistance inner resistance antibiotic resistance resistance to a disease (see related subject immunology) a political or military resistance movement against foreign occupation, or more rarely, against ones own government geological resistance fluid resistance thermal resistance Resistance Records Air resistance This is a disambiguation...


Applications

Silicon is a very useful element that is vital to many human industries. Silicon dioxide in the form of sand and clay is an important ingredient of concrete and brick and is also used to produce Portland cement. Silicon is a very important element for plant and animal life. Diatoms extract silica from water to build their protective cell walls. Other uses: The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ... Patterns in the sand Sand is an example of a class of materials called granular matter. ... Clay is a generic term for an aggregate of hydrous silicate particles less than 4 μm (micrometres) in diameter. ... This article is about the construction material. ... This page is about bricks used for construction. ... Insert non-formatted text here--213. ... Divisions Land plants (embryophytes) Non-vascular plants (bryophytes) Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants Adiantum pedatum (a fern... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Subregnum Bilateria  Acoelomorpha  Orthonectida  Rhombozoa  Myxozoa  Superphylum Deuterostomia     Chordata (vertebrates, etc. ... Diatoms are a major group of eukaryotic algae, and are one of the most common types of phytoplankton. ...

  • Pottery/Enamel - It is a refractory material used in high-temperature material production and its silicates are used in making enamels and pottery.
  • Steel - Silicon is an important constituent of some steels.
  • Bronze - Most bronze produced is an alloy of copper and silicon.
  • Glass - Silica from sand is a principal component of glass. Glass can be made into a great variety of shapes and with a many different physical properties. Silica is used as a base material to make window glass, containers, and insulators, and many other useful objects.
  • Abrasives - Silicon carbide is one of the most important abrasives.
  • Semiconductor - Ultrapure silicon can be doped with other elements to adjust its electrical response by controlling the number and charge (positive or negative) of current carriers. Such control is necessary for transistors, solar cells and other semiconductor devices which are used in electronics and other high-tech applications.
  • Photonics - Silicon can be used as a continuous wave raman laser to produce coherent light with a wavelength of 1,698 nm.
  • Medical materials - Silicones are flexible compounds containing silicon-oxygen and silicon-carbon bonds; they are widely used in applications such as artificial breast implants and contact lenses.
  • LCDs and solar cells - Hydrogenated amorphous silicon has shown promise in the production of low-cost, large-area electronics in applications such as LCDs. It has also shown promise for large-area, low-cost solar cells.
  • Construction - Silica is a major ingredient in bricks because of its low chemical activity.

A man shapes pottery as it turns on a wheel. ... In a discussion of art or technology, enamel (or vitreous enamel, or porcelain enamel in American English) is the colorful result of fusion of powdered glass to a substrate through the process of firing, usually between 750 and 850 degrees Celsius. ... // Steel is a metal alloy whose major component is iron, with carbon being the primary alloying material. ... Bronze figurine, found at Öland Bronze is the traditional name for a broad range of alloys of copper. ... An alloy is a combination, either in solution or compound, of two or more elements, at least one of which is a metal, and where the resultant material has metallic properties. ... General Name, Symbol, Number copper, Cu, 29 Chemical series transition metals Group, Period, Block 11, 4, d Appearance copper, metallic Atomic mass 63. ... The materials definition of a glass is a uniform amorphous solid material, usually produced when a suitably viscous molten material cools very rapidly, thereby not giving enough time for a regular crystal lattice to form. ... Insulators are materials which prevent the flow of heat (thermal insulators) or electric charge (electrical insulators). ... An abrasive is a usually rough object that is used to smooth another through extensive rubbing. ... Silicon carbide (SiC), also known as carborundum or moissanite, is a ceramic compound of silicon and carbon. ... Derka semiconductor is a material with an electrical conductance that is intermediate between that of an insulator and a conductor. ... In semiconductor production, doping refers to the process of intentionally introducing impurities into an intrinsic semiconductor in order to change its electrical properties. ... In solid state physics, an electron hole (usually referred to simply as a hole) is the absence of an electron from the otherwise full valence band. ... Properties The electron is a fundamental subatomic particle which carries a negative electric charge. ... Through hole transistors (tape measure marked in centimeters) The transistor is a solid state semiconductor device which can be used for amplification, switching, voltage stabilization, signal modulation and many other functions. ... A solar cell, or photovoltaic cell, is a semiconductor device consisting of a large-area p-n junction diode, which, in the presence of sunlight is capable of generating usable electrical energy. ... Semiconductor devices are electronic components that exploit the electronic properties of semiconductor materials, principally silicon, germanium, and gallium arsenide. ... This article is in need of attention from an expert on the subject. ... Laser (US Air Force) A LASER (Light Amplification by Stimulated Emission of Radiation) is an optical device which uses a quantum mechanical effect called stimulated emission (discovered by Einstein while researching the photoelectric effect) in order to generate a coherent beam of light from a lasing medium of controlled purity... Silicones, or polysiloxanes, are inorganic polymers consisting of a silicon-oxygen backbone (...-Si-O-Si-O-Si-O-...) with side groups attached to the silicon atoms. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... Breast implant diagram Silicone gel-filled breast implants Saline-filled breast implants A breast implant is a prosthesis used in cosmetic surgery to enhance the size and shape of a womans breasts (known as breast augmentation) or to reconstruct the breast (for example, after a mastectomy, or during male... Reflective twisted nematic liquid crystal display. ... A solar cell, or photovoltaic cell, is a semiconductor device consisting of a large-area p-n junction diode, which, in the presence of sunlight is capable of generating usable electrical energy. ... Amorphous silicon (a-Si) is the non-crystalline form of silicon. ... Roll-to-roll processing, also known as web processing, is the process of creating electronic devices on a roll of flexible plastic or metal foil. ... Cranes are essential in construction, as seen in this photo of the construction of a skyscraper Construction on the North Bytown Bridge in Ottawa, Canada. ...

History

Silicon (Latin silex, silicis meaning flint) was first identified by Antoine Lavoisier in 1787, and was later mistaken by Humphry Davy in 1800 for a compound. In 1811 Gay Lussac and Thénard probably prepared impure amorphous silicon through the heating of potassium with silicon tetrafluoride. In 1824 Berzelius prepared amorphous silicon using approximately the same method of Lussac. Berzelius also purified the product by repeatedly washing it. Latin is the language originally spoken in the region around Rome called Latium. ... Pebble beach made up of flint nodules eroded out of the nearby chalk cliffs, Cape Arkona, Rügen Flint (or flintstone) is a hard, sedimentary cryptocrystalline silica rock with a glassy appearance. ... Portrait of Monsieur Lavoisier and his Wife, by Jacques-Louis David Antoine-Laurent de Lavoisier (August 26, 1743 – May 8, 1794) was a French nobleman prominent in the histories of chemistry, finance, biology, and economics. ... 1787 was a common year starting on Monday (see link for calendar). ... Humphry Davy Sir Humphry Davy (December 17, 1778 - May 29, 1829), often incorrectly spelled Humphrey, was a Cornish chemist. ... 1800 was a common year starting on Wednesday (see link for calendar). ... 1811 was a common year starting on Tuesday (see link for calendar). ... Joseph-Louis Gay-Lussac (December 6, 1778–May 10, 1850) was a French chemist and physicist. ... Louis Jacques Thénard. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance silvery white Atomic mass 39. ... 1824 was a leap year starting on Thursday (see link for calendar). ... Jöns Jakob Berzelius (August 20, 1779 - August 7, 1848) was a Swedish chemist, who invented modern chemical notation and is considered one of the fathers of modern chemistry (along with John Dalton and Antoine Lavoisier). ...


Because silicon is an important element in semiconductor and high-tech devices, the high-tech region of Silicon Valley, California, is named after this element. A view of downtown San Jose, the self-proclaimed Capital of Silicon Valley. Like many large cities, San Joses downtown is expansive and encompasses much more area than shown in this view. ... State nickname: The Golden State Other U.S. States Capital Sacramento Largest city Los Angeles Governor Arnold Schwarzenegger (R) Official languages English Area 410,000 km² (3rd)  - Land 404,298 km²  - Water 20,047 km² (4. ...


Occurrence

Silicon is a principal component of aerolites which are a class of meteoroids and also of tektites which is a natural form of glass. A meteoroid is a relatively small (sand- to boulder-sized) fragment of debris in the Solar System. ... A tektite Tektites (from Greek tektos, molten) are natural glass objects, up to a few centimeters in size, which — according to most scientists — have been formed by the impact of large meteorites on Earths surface, although a few researchers favor an origin from the Moon as volcanic ejecta. ...


Measured by weight, silicon makes up 25.7% of the earth's crust and after oxygen is also the second most abundant element. Elemental silicon is not found in nature. It occurs most often as oxides and as silicates. Sand, amethyst, agate, quartz, rock crystal, flint, jasper, and opal are some of the forms in which the oxide appears. Granite, asbestos, feldspar, clay, hornblende, and mica are a few of the many silicate minerals. Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third-closest planet to the Sun. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... An oxide is a chemical compound of oxygen with other chemical elements. ... Patterns in the sand Sand is an example of a class of materials called granular matter. ... Amethyst is a violet or purple variety of quartz often used as an ornament. ... Quartz is the most abundant mineral in the Earths crust. ... Jasper pebble, one inch (2. ... OPAL is also the name of one of the four detectors of the Large Electron-Positron Collider. ... Quarrying granite for the Mormon Temple, Utah Territory. ... Asbestos (Greek a-, not; sbestos, extinguishable) is a group of fibrous metamorphic minerals. ... Feldspar is the name of an important group of rock-forming minerals which make up perhaps as much as 60% of the Earths crust. ... Amphibole (Hornblende) The mineral hornblende is a complex silicate which is an isomorphous mixture of three molecules; a calcium-iron-magnesium silicate, an aluminium-iron-magnesium silicate, and an iron-magnesium silicate. ... rock with mica Mica sheet mica flakes The mica group of minerals includes several closely related materials having highly perfect basal cleavage. ... This article is about minerals in the geologic sense; for nutrient minerals see dietary mineral; for the band see Mineral (band). ...


Production

Silicon is commercially prepared by the heating of high-purity silica in an electric arc furnace using carbon electrodes. At temperatures over 1900 °C, the carbon reduces the silica to silicon according to the chemical equation General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... An electrode is a conductor used to make contact with a nonmetallic part of a circuit (e. ... This article needs to be cleaned up to conform to a higher standard of quality. ...

SiO2 + C → Si + CO2

Liquid silicon collects in the bottom of the furnace, and is then drained and cooled. The silicon produced via this process is called metallurgical grade silicon and is at least 99% pure. Using this method, silicon carbide, SiC, can form. However, provided the amount of SiO2 is kept high, silicon carbide may be eliminated, as explained by this equation:

2SiC + SiO2 → 3Si + 2CO

In 2000, metallurgical grade silicon cost about $ 0.56 per pound ($1.23/kg).[1]. The United States dollar, or American dollar, is the official currency of the United States. ...

Silicon wafer with mirror finish (NASA)
Silicon wafer with mirror finish (NASA)

Image File history File links Date: 02. ... Image File history File links Date: 02. ...

Purification

The use of silicon in semiconductor devices demands a much greater purity than afforded by metallurgical grade silicon. Historically, a number of methods have been used to produce high-purity silicon. Derka semiconductor is a material with an electrical conductance that is intermediate between that of an insulator and a conductor. ...


Physical methods

Early silicon purification techniques were based on the fact that if silicon is melted and re-solidified, the last parts of the mass to solidify contain most of the impurities. The earliest method of silicon purification, first described in 1919 and used on a limited basis to make radar components during World War II, involved crushing metallurgical grade silicon and then partially dissolving the silicon powder in an acid. When crushed, the silicon cracked so that the weaker impurity-rich regions were on the outside of the resulting grains of silicon. As a result, the impurity-rich silicon was the first to be dissolved when treated with acid, leaving behind a more pure product. This long range radar antenna (approximately 40m (130ft) in diameter) rotates on a track to observe activities near the horizon. ... World War II was a truly global conflict with many facets: immense human suffering, fierce indoctrinations, and the use of new, extremely devastating weapons like the atom bomb World War II, also known as the Second World War, was a mid-20th-century conflict that engulfed much of the globe... An acid (often represented by the generic formula AH) is typically a water-soluble, sour-tasting chemical compound. ...


In zone melting, the first silicon purification method to be widely used industrially, rods of metallurgical grade silicon are heated to melt at one end. Then, the heater is slowly moved down the length of the rod, keeping a small length of the rod molten as the silicon cools and resolidifies behind it. Since most impurities tend to remain in the molten region rather than resolidify, when the process is complete, most of the impurities in the rod will have been moved into the end that was the last to be melted. This end is then cut off and discarded, and the process repeated if a still higher purity was desired. Zone melting is a method of separation by melting in which a series of molten zones traverses a long ingot of impure metal or chemical. ...


Chemical methods

Today, silicon is instead purified by converting it to a silicon compound that can be more easily purified than silicon itself, and then converting that silicon compound back into pure silicon. Trichlorosilane is the silicon compound most commonly used as the intermediate, although silicon tetrachloride and silane are also used. When these gases are blown over silicon at high temperature, they decompose to high-purity silicon. A chemical compound is a chemical substance formed from two or more elements, with a fixed ratio determining the composition. ... Trichlorosilane is a chemical compound containing silicon, hydrogen, and chlorine. ... Silicon tetrachloride (SiCl4) is a colourless volatile liquid. ... Silane is a chemical compound with chemical formula SiH4. ...


In the Siemens process, high-purity silicon rods are exposed to trichlorosilane at 1150 °C. The trichlorosilane gas decomposes and deposits additional silicon onto the rods, enlarging them according to chemical reactions like A chemical reaction is a process involving one, two or more substances (called reactants), characterized by a chemical change and yielding one or more product(s) which are different from the reactants. ...

2 HSiCl3 → Si + 2 HCl + SiCl4

Silicon produced from this and similar processes is called polycrystalline silicon. Polycrystalline silicon typically has impurity levels of 1 part per billion or less.


At one time, DuPont produced ultrapure silicon by reacting silicon tetrachloride with high-purity zinc vapors at 950 °C, producing silicon according to the chemical equation This article is about the DuPont company. ... General Name, Symbol, Number zinc, Zn, 30 Chemical series transition metals Group, Period, Block 12, 4, d Appearance bluish pale gray Atomic mass 65. ...

SiCl4 + 2 Zn → Si + 2 ZnCl2

However, this technique was plagued with practical problems (such as the zinc chloride byproduct solidifying and clogging lines) and was eventually abandoned in favor of the Siemens process. Zinc chloride (ZnCl2) is a colorless or white compound of zinc and chlorine that is extremely hygroscopic. ...


Crystallization

The majority of silicon crystals grown for device production are produced by the Czochralski process, since it is the cheapest method available. However, silicon single-crystals grown by the Czochralski method contain impurities since the crucible which contains the melt dissolves. For certain electronic devices, particularly those required for high power applications, silicon grown by the Czochralski method is not pure enough. For these applications, float-zone silicon (FZ-Si) can be used instead. The Czochralski process is a method of crystal growth used to obtain single crystals of semiconductors, metals (e. ... For other uses of crucible, see Crucible (disambiguation) Categories: Alchemical apparatus ... Float-zone silicon is a high-purity alternative to silicon grown by the Czochralski process. ...


Isotopes

Silicon has nine isotopes, with mass numbers from 25-33. Si-28 (the most abundant isotope, at 92.23%), Si-29 (4.67%), and Si-30 (3.1%) are stable; Si-32 is a radioactive isotope produced by argon decay. Its half-life, has been determined to be approximately 132 years, and it decays by beta emission to P-32 (which has a 14.28 day half-life [2]) and then to S-32. Isotopes are forms of an element whose nuclei have the same atomic number–-the number of protons in the nucleus--but different atomic masses because they contain different numbers of neutrons. ... The mass number (A), also called atomic mass number or nucleon number, is the number of protons and neutrons in an atomic nucleus. ... Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles. ... General Name, Symbol, Number argon, Ar, 18 Chemical series noble gases Group, Period, Block 18, 3, p Appearance colorless Atomic mass 39. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... In nuclear physics, beta decay (sometimes called neutron decay) is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. ... This article is about the chemical element. ... General Name, Symbol, Number sulfur, S, 16 Chemical series nonmetals Group, Period, Block 16, 3, p Appearance lemon yellow Atomic mass 32. ...


Precautions

A serious lung disease known as silicosis often occurred in miners, stonecutters, and others who were engaged in work where siliceous dust was inhaled in great quantities. A disease is any abnormal condition of the body or mind that causes discomfort, dysfunction, or distress to the person affected or those in contact with the person. ... Pneumoconiosis is a lung condition caused by the inhalation of dust, characterized by formation of nodular fibrotic changes in lungs. ... The El Chino Mine located near Silver City, New Mexico is an open-pit copper mine Mining is the extraction of valuable minerals or other geological materials from the earth, usually (but not always) from an ore body, vein, or (coal) seam. ... The Sacred Order of the Stonecutters is a fictional secret society from the animated television show The Simpsons conceived of as a parody of secret societies in general, and Freemasonry in particular. ...


Silicon is not silicone

Casual speakers often make the mistake of interchanging the words silicon and silicone; they are not the same. The first, of course, is the element that is the topic of this article. The second is a class of chemical compounds (in particular, inorganic polymers) that contain the element silicon, the most notable members of the class being silicone rubbers and silicone gels. Silicones, or polysiloxanes, are inorganic polymers consisting of a silicon-oxygen backbone (...-Si-O-Si-O-Si-O-...) with side groups attached to the silicon atoms. ... A chemical compound is a chemical substance formed from two or more elements, with a fixed ratio determining the composition. ...


Silicon-based life

Since Silicon is analogous to Carbon, some scientists have proposed the possibility of Silicon-based life. This concept is especially popular in science-fiction. Alternative biochemistry collectively refers to an assortment of astrobiology theories and hypotheses in which life is based on chemical systems other than those used by currently known forms of life. ...


References

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