{"id":193,"date":"2012-05-22T13:49:06","date_gmt":"2012-05-22T13:49:06","guid":{"rendered":"http:\/\/www.chemicool.com\/elements\/?page_id=193"},"modified":"2017-12-07T02:08:38","modified_gmt":"2017-12-07T07:08:38","slug":"silicon","status":"publish","type":"page","link":"https:\/\/www.chemicool.com\/elements\/silicon.html","title":{"rendered":"Silicon Element Facts"},"content":{"rendered":"<div class=\"insidepagelinks\">\n<a href=\"#data\">Data Zone<\/a> |  <a href=\"#discovery\">Discovery<\/a> |  <a href=\"#facts\">Facts<\/a> | <a href=\"#appear\">Appearance &amp; Characteristics<\/a> | <a href=\"#uses\">Uses<\/a> | <a href=\"#abund\">Abundance &amp; Isotopes<\/a>  | <a href=\"#refer\">References<\/a>\n<\/div>\n<div class=\"metalloidT\">\n<div class=\"atnorT\">14<\/div>\n<div class=\"clearT\"><\/div>\n<div class=\"elnamT\">Si<\/div>\n<div class=\"atweiT\">28.09<\/div>\n<\/div>\n<p>The chemical element silicon is classed as a metalloid. It was discovered in 1824 by Jacob Berzelius.<\/p>\n<div style=\"clear:both;\"><\/div>\n<div class=\"adsense300\">\n<div class=\"adsense300spacer\">\n<div style=\"line-height:10px;\"><img decoding=\"async\" src=\"\/\/www.chemicool.com\/ad.png\" alt=\"\" \/><\/div>\n<p><script async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script><ins class=\"adsbygoogle\" style=\"display: block;\" data-ad-client=\"ca-pub-9461632227417539\" data-ad-slot=\"8753977201\" data-ad-format=\"auto\"><\/ins><script>(adsbygoogle = window.adsbygoogle || []).push({});<\/script><\/p>\n<p><a id=\"data\"><\/a><\/p>\n<h2>Data Zone<\/h2>\n<table class=\"datatop\">\n<tr>\n<td class=\"elemglb\">Classification:<\/td>\n<td> Silicon is a metalloid  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Color:<\/td>\n<td>  silvery   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Atomic weight:<\/td>\n<td>   28.0855 <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">State:<\/td>\n<td>   solid   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Melting point:<\/td>\n<td> 1414 <sup>o<\/sup>C, 1687 K    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Boiling point:<\/td>\n<td>  3265 <sup>o<\/sup>C, 3538 K    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electrons:<\/td>\n<td>14<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Protons:<\/td>\n<td>14<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Neutrons in most abundant isotope:<\/td>\n<td>14<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron shells:<\/td>\n<td>   2,8,4  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron configuration:<\/td>\n<td>  1s<sup>2<\/sup> 2s<sup>2<\/sup> 2p<sup>6<\/sup> 3s<sup>2<\/sup> 3p<sup>2<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Density @ 20<sup>o<\/sup>C:<\/td>\n<td>  2.33 g\/cm<sup>3<\/sup>  <\/td>\n<\/tr>\n<\/table>\n<span class=\"collapseomatic \" id=\"id69e17afd01f38\"  tabindex=\"0\" title=\"Show more, including: Heats, Energies, Oxidation,&lt;br \/&gt; Reactions, Compounds, Radii, Conductivities\"    >Show more, including: Heats, Energies, Oxidation,<br \/> Reactions, Compounds, Radii, Conductivities<\/span><div id=\"target-id69e17afd01f38\" class=\"collapseomatic_content \">\n<table class=\"datatop\">\n<tr>\n<td class=\"elemglb\">Atomic volume:<\/td>\n<td>  12.1 cm<sup>3<\/sup>\/mol   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Structure:<\/td>\n<td>   diamond structure <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Hardness: <\/td>\n<td>    7 mohs  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Specific heat capacity<\/td>\n<td>  0.71 J g<sup>-1<\/sup> K<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of fusion<\/td>\n<td> 50.21 kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of atomization<\/td>\n<td> 456 kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of vaporization<\/td>\n<td>   359  kJ mol<sup>-1<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">1<sup>st<\/sup> ionization energy<\/td>\n<td>  786.4 kJ mol<sup>-1<\/sup>    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">2<sup>nd<\/sup> ionization energy<\/td>\n<td>  1577 kJ mol<sup>-1<\/sup>    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">3<sup>rd<\/sup> ionization energy<\/td>\n<td>   3231.4 kJ mol<sup>-1<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron affinity<\/td>\n<td>   133.6 kJ mol<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Minimum oxidation number<\/td>\n<td>  -4    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Min. common oxidation no.<\/td>\n<td>  -4   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Maximum oxidation number <\/td>\n<td> 4 <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Max. common oxidation no. <\/td>\n<td>  4  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Electronegativity (Pauling Scale) <\/td>\n<td> 1.9  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Polarizability volume <\/td>\n<td>   5.4 &Aring;<sup>3<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with air<\/td>\n<td> none   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with 15 M HNO<sub>3<\/sub> <\/td>\n<td>  none  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with 6 M HCl <\/td>\n<td>  none <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with 6 M NaOH <\/td>\n<td>    mild, &#8658;  silicates  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Oxide(s) <\/td>\n<td> SiO<sub>2<\/sub>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Hydride(s) <\/td>\n<td>   SiH<sub>4<\/sub> (silane),  Si<sub>2<\/sub>H<sub>6<\/sub> + more <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Chloride(s) <\/td>\n<td>  SiCl<sub>4<\/sub>,  Si<sub>2<\/sub>Cl<sub>6<\/sub> + more <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Atomic radius <\/td>\n<td>   110 pm  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Ionic radius (1+ ion) <\/td>\n<td> &#8211; <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Ionic radius (2+ ion) <\/td>\n<td>   &#8211;  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Ionic radius (3+ ion) <\/td>\n<td> &#8211; <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Ionic radius (1- ion) <\/td>\n<td>   &#8211;  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Ionic radius (2- ion) <\/td>\n<td> &#8211; <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Ionic radius (3- ion) <\/td>\n<td>   &#8211;  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Thermal conductivity <\/td>\n<td>149 W m<sup>-1<\/sup> K<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Electrical conductivity <\/td>\n<td>  4 x 10<sup>2<\/sup> S m<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Freezing\/Melting point:<\/td>\n<td> 1414 <sup>o<\/sup>C, 1687 K    <\/td>\n<\/tr>\n<\/table>\n<\/div>\n<\/div>\n<div class=\"leftimagepadding\">\n<div style=\"width: 310px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.chemicool.com\/elements\/images\/300-silicon-pure.jpg\" width=\"300\" height=\"213\" alt=\"Pure Silicon.\" class=\"size-full\" \/><p class=\"wp-caption-text\">Pure Silicon. Photo by Enricoros<\/p><\/div>\n<div style=\"width: 310px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/chemicool.com\/elements\/images\/300-siliconcrystal.png\" width=\"300\" height=\"160\" alt=\"Silicon crystal structure.\" class=\"size-full\" \/><p class=\"wp-caption-text\">Silicon crystal structure.<\/p><\/div>\n<\/div>\n<\/div>\n<p><a id=\"discovery\"><\/a><\/p>\n<h2>Discovery of Silicon<\/h2>\n<div class=\"author\">Dr. Doug Stewart<\/div>\n<p>    Quartz (crystalline silicon dioxide) has been known to people for many thousands of years. Flint is a form of quartz, and tools made from flint were in everyday use in the stone age.<\/p>\n<p>\t\t In 1789, the French chemist Antoine Lavoisier proposed that a new chemical element could be found in quartz. This new element, he said, must be very abundant. <sup>(1)<\/sup> He was right, of course. Silicon accounts for 28% of the weight of Earth&#8217;s crust.<\/p>\n<p>\t\t It is possible that in England, in 1808, Humphry Davy isolated partly pure silicon for the first time, but he did not realize it. <sup>(2)<\/sup><\/p>\n<p>\t\tIn 1811, French chemists Joseph L. Gay-Lussac and Louis Jacques Th&eacute;nard may also have made impure silicon by reacting <a href=\"https:\/\/www.chemicool.com\/elements\/potassium.html\">potassium<\/a> with silicon tetrafluoride to produce a reddish brown solid which was probably amorphous silicon. They did not, however, attempt to purify this new substance.  <sup>(3), (4)<\/sup><\/p>\n<p>\t\t In 1824, Swedish chemist Jacob Berzelius produced a sample of amorphous silicon, a brown solid, by reacting potassium fluorosilicate with <a href=\"https:\/\/www.chemicool.com\/elements\/potassium.html\">potassium<\/a> and purifying the product with repeated washing. He named the new element <i>silicium<\/i>. <sup>(3), (4)<\/sup><\/p>\n<p>\t\t At that time the concept of semiconductors lay a century in the future. Unaware that such materials existed and that silicon was an excellent example of a semiconductor, scientists debated whether the new element should be classed as a metal or a nonmetal.<\/p>\n<p>\t\t Berzelius believed it was a metal, while Humphry Davy thought it was a nonmetal. <sup>(5)<\/sup> &nbsp; The problem was that the new element was a better conductor of electricity than nonmetals, but not as good a conductor as a metal.<\/p>\n<p>\t\tSilicon was given its name in 1831 by Scottish chemist Thomas Thomson. He retained part of Berzelius&#8217;s name, from &#8216;silicis,&#8217; meaning flint. He changed the element&#8217;s ending to <i>on<\/i> because the element was more similar to nonmetals <a href=\"boron.html\">boron<\/a> and <a href=\"carbon.html\">carbon<\/a> than it was to metals such as <a href=\"https:\/\/www.chemicool.com\/elements\/calcium.html\">calcium<\/a> and <a href=\"https:\/\/www.chemicool.com\/elements\/magnesium.html\">magnesium<\/a>. (Silicis, or flint, was probably our first use of silicon dioxide. <sup>(4), (6)<\/sup>)<\/p>\n<p>\t\t In 1854, Henri Deville produced crystalline silicon for the first time. He did this by electrolyzing an impure melt of sodium aluminum chloride to produce aluminum silicide. The <a href=\"https:\/\/www.chemicool.com\/elements\/aluminum.html\">aluminum<\/a> was removed with water, leaving silicon crystals. <sup>(4)<\/sup>\t<\/p>\n<p><a id=\"facts\"><\/a><\/p>\n<h2>Interesting Facts about  Silicon<\/h2>\n<ul>\n<li>\n   The lowest acceptable purity for electronic grade silicon is 99.9999999%. This means that for every billion atoms, only one non-silicon atom is allowed.\n  <\/li>\n<li>\n   Silicon is the second most abundant element in our planet&#8217;s crust. Oxygen (47.3%) and silicon (27.7%) together make up 75% of the weight of Earth&#8217;s crust. Most of the crust&#8217;s silicon exists as silicon dioxide; we are familiar with this as sand or quartz.\n <\/li>\n<li>\n   Silicon is the eighth most abundant element in the Universe; it is made in stars with a mass of eight or more Earth suns. Near the end of their lives these stars enter the carbon burning phase, adding helium nuclei to carbon to produce oxygen, neon, magnesium and silicon.\n <\/li>\n<li>\n   Silicon burning is the last phase of a heavy star&#8217;s life before a supernova and lasts only about one day. During this phase, helium nuclei add to silicon to make sulfur, argon, calcium, titanium, chromium, iron and nickel.\n <\/li>\n<\/ul>\n<div style=\"clear: both; line-height: 20px;\">&nbsp;<\/div>\n<div class=\"adsense300\">\n<div class=\"adsense300spacer\">\n<div style=\"line-height: 10px;\"><img decoding=\"async\" src=\"\/\/www.chemicool.com\/ad.png\" alt=\"\" \/><\/div>\n<p><script async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script><ins class=\"adsbygoogle\" style=\"display: inline-block; width: 336px; height: 280px;\" data-ad-client=\"ca-pub-9461632227417539\" data-ad-slot=\"2986645201\"><\/ins><script>(adsbygoogle = window.adsbygoogle || []).push({});<\/script><\/p>\n<div class=\"leftimagepadding\">\n<p><iframe loading=\"lazy\" width=\"300\" height=\"233\" src=\"https:\/\/www.youtube.com\/embed\/aWVywhzuHnQ\" allowfullscreen><\/iframe><\/p>\n<div class=\"youtubecaption\">How silicon is made into wafers and computer chips. <\/div>\n<p><iframe loading=\"lazy\" width=\"300\" height=\"233\" src=\"https:\/\/www.youtube.com\/embed\/BUq2bQkL1zo\" allowfullscreen><\/iframe><\/p>\n<div class=\"youtubecaption\">Not only about silicon: how the next generation of electronic devices may work.<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p><a id=\"appear\"><\/a><\/p>\n<h3>Appearance and Characteristics<\/h3>\n<p>  <strong>Harmful effects:<\/strong> <\/p>\n<p>\t \tSilicon is not known to be toxic, but if breathed in as a fine silica\/silicate dust it may cause chronic respiratory problems.  Silicates such as asbestos are carcinogenic.<\/p>\n<p>\t\t<strong>Characteristics:<\/strong><\/p>\n<p>\t\t Silicon is a hard, relatively inert metalloid and in crystalline form is very brittle with a marked metallic luster.<\/p>\n<p>\t\tSilicon  occurs mainly in nature as the oxide and as silicates.<\/p>\n<p>\t\tThe solid form of silicon does not react with <a href=\"https:\/\/www.chemicool.com\/elements\/oxygen.html\">oxygen<\/a>, water and most acids.<\/p>\n<p>\t\tSilicon reacts with halogens or dilute alkalis. <\/p>\n<p>\t\tSilicon also has the unusual property that (like water) it expands as it freezes. <\/p>\n<p>\t\tFour other elements expand when they freeze; <a href=\"https:\/\/www.chemicool.com\/elements\/gallium.html\">gallium<\/a>, <a href=\"https:\/\/www.chemicool.com\/elements\/bismuth.html\">bismuth<\/a>, <a href=\"https:\/\/www.chemicool.com\/elements\/antimony.html\">antimony<\/a> and <a href=\"https:\/\/www.chemicool.com\/elements\/germanium.html\">germanium<\/a><\/p>\n<p><a id=\"uses\"><\/a><\/p>\n<h2>Uses of Silicon<\/h2>\n<p>\t\tSilicon chips are the basis of modern electronic and computing. The silicon must be ultrapure, although depending on final use it may be doped with part per million levels of <a href=\"https:\/\/www.chemicool.com\/elements\/arsenic.html\">arsenic<\/a>, <a href=\"https:\/\/www.chemicool.com\/elements\/boron.html\">boron<\/a>, <a href=\"https:\/\/www.chemicool.com\/elements\/gallium.html\">gallium<\/a>, <a href=\"https:\/\/www.chemicool.com\/elements\/germanium.html\">germanium<\/a>, or <a href=\"https:\/\/www.chemicool.com\/elements\/phosphorus.html\">phosphorus<\/a>.<\/p>\n<p>\t\tSilicon is alloyed with <a href=\"https:\/\/www.chemicool.com\/elements\/aluminum.html\">aluminum<\/a> for use in engines as the presence of silicon improves the metal&#8217;s castability. Silicon can enhance <a href=\"https:\/\/www.chemicool.com\/elements\/iron.html\">iron&#8217;s<\/a> magnetic properties; it is also an important component of steel, which it toughens.<\/p>\n<p>\t\tSilicon carbide, more commonly called carborundum, is extremely hard and is used in abrasives.<\/p>\n<p>\t\tSilica (SiO<sub>2<\/sub>) in sand and minerals in clay is used to make concrete and bricks. Silica, as sand, is also the main constituent of glass.<\/p>\n<p>\t\tPure, crystalline silicon dioxide (quartz) resonates at a very precise frequency and is used in high-precision watches and clocks.<\/p>\n<p>\t\tSilicones are important silicon based polymers. Having heat-resistant, nonstick, and rubber-like properties, silicones are often used in cookware, medicine (implants), and as sealants, adhesives, lubricants, and for insulation. <\/p>\n<p><a id=\"abund\"><\/a><\/p>\n<h2>Abundance and Isotopes<\/h2>\n<p><span class=\"elemgl\">Abundance earth&#8217;s crust:<\/span>   28 % by weight, 21 % ppm by moles<\/p>\n<p>\t\t<span class=\"elemgl\">Abundance solar system:<\/span> 900 parts per million by weight, 40 parts per million by moles<\/p>\n<p>\t\t\t\t<span class=\"elemgl\">Cost, pure:<\/span> $5.4 per 100g<\/p>\n<p>\t\t\t\t<span class=\"elemgl\">Cost, bulk:<\/span>  $0.14 per 100g<\/p>\n<p>\t\t<span class=\"elemgl\">Source:<\/span> Silicon is the second most abundant element in Earth&#8217;s crust, after <a href=\"https:\/\/www.chemicool.com\/elements\/oxygen.html\">oxygen<\/a> and the eighth most abundant in the Universe. It is most commonly found as silicon dioxide (silica). Two elements, silicon and oxygen, make up almost three-quarters of our planet&#8217;s crust. <\/p>\n<p>\t   Commercial quantities of silicon are obtained by the reaction of silicon dioxide and carbon in an electric furnace using <a href=\"https:\/\/www.chemicool.com\/elements\/carbon.html\">carbon<\/a> electrodes. The carbon reduces the silicon dioxide to silicon. Silicon produced in this way is about 98% pure.<\/p>\n<p>\t\t Very high purity silicon for semiconductors is obtained using the Siemens process; the silicon is reacted to produce trichlorosilane, which is first purified by distillation, then reacted with purified <a href=\"https:\/\/www.chemicool.com\/elements\/hydrogen.html\">hydrogen<\/a> on high purity silicon rods at 1150 <sup>o<\/sup>C to yield high purity, polycrystalline silicon with hydrochloric acid byproduct. Impurities in the silicon are about 1 part per billion or less. <\/p>\n<p>\t\t<span class=\"elemgl\">Isotopes:<\/span> Silicon has 14 isotopes whose half-lives are known, with mass numbers 22 to 36. Naturally occurring silicon is a mixture of its three stable isotopes and they are found in the percentages shown: <sup>28<\/sup>Si (92.2%), <sup>29<\/sup>Si (4.7%) and <sup>30<\/sup>Si (3.1%).<\/p>\n<div style=\"max-width: 750px;\">\n<div style=\"line-height: 10px;\"><img decoding=\"async\" src=\"\/\/www.chemicool.com\/ad.png\" alt=\"\" \/><\/div>\n<p><script async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script><ins class=\"adsbygoogle\" style=\"display: block;\" data-ad-client=\"ca-pub-9461632227417539\" data-ad-slot=\"8753977201\" data-ad-format=\"auto\"><\/ins><script>(adsbygoogle = window.adsbygoogle || []).push({});<\/script><\/p>\n<\/div>\n<p><a id=\"refer\"><\/a><\/p>\n<h4>References<\/h4>\n<ol>\n<li>R.W. Cahn, <a href=\"http:\/\/adsabs.harvard.edu\/abs\/2009LNES..106....3C\">Silicon: Child and Progenitor of Revolution<\/a>., Into The Nano Era, Springer Series in Materials Science, Volume 106. (2009) p3. <\/li>\n<li>Thomas Edward Thorpe, <a href=\"http:\/\/www.archive.org\/stream\/humphrydavypoetp00thoruoft#page\/128\/mode\/2up\">Humphry Davy, Poet and Philosopher.,<\/a> (1896).<\/li>\n<li> Mary Elvira Weeks, Discovery of the Elements., (2003) p162, Kessinger Publishing Reprints.<\/li>\n<li> John Emsley, Nature&#8217;s Building Blocks: An A-Z Guide to the Elements., (2002) p387. Oxford University Press. \t<\/li>\n<li> H. R. Huff, U. G&#246;sele, H. Tsuya, Semiconductor Silicon., (1998) p70, The Electrochemical Society. <\/li>\n<li> Keith B. Hutton, Chemistry. (2001) p224. Routledge.<\/li>\n<\/ol>\n<h4>Cite this Page<\/h4>\n<p>For online linking, please copy and paste one of the following:<\/p>\n<pre class='code'>\r\n&lt;a href=\"https:\/\/www.chemicool.com\/elements\/silicon.html\"&gt;Silicon&lt;\/a&gt;\r\n<\/pre>\n<p>or<\/p>\n<pre class='code'>\r\n&lt;a href=\"https:\/\/www.chemicool.com\/elements\/silicon.html\"&gt;Silicon Element Facts&lt;\/a&gt;\r\n<\/pre>\n<p>To cite this page in an academic document, please use the following MLA compliant citation:<\/p>\n<pre class='code'>\r\n\"Silicon.\" Chemicool Periodic Table. Chemicool.com. 09 Oct. 2012. Web. <script type=\"text\/javascript\">\r\n<!--\r\nvar currentTime = new Date()\r\nvar month = currentTime.getMonth() + 1\r\nvar day = currentTime.getDate()\r\nvar year = currentTime.getFullYear()\r\ndocument.write(month + \"\/\" + day + \"\/\" + year)\r\n\/\/-->\r\n<\/script> \r\n&lt;https:\/\/www.chemicool.com\/elements\/silicon.html&gt;.<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Data Zone | Discovery | Facts | Appearance &amp; Characteristics | Uses | Abundance &amp; Isotopes | References 14 Si 28.09 The chemical element silicon is classed as a metalloid. It was discovered in 1824 by Jacob Berzelius. Data Zone Classification: Silicon is a metalloid Color: silvery Atomic weight: 28.0855 State: solid Melting point: 1414 [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"class_list":{"0":"post-193","1":"page","2":"type-page","3":"status-publish","5":"entry"},"_links":{"self":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/193","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/comments?post=193"}],"version-history":[{"count":21,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/193\/revisions"}],"predecessor-version":[{"id":4301,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/193\/revisions\/4301"}],"wp:attachment":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/media?parent=193"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}