{"id":417,"date":"2012-05-25T12:41:10","date_gmt":"2012-05-25T12:41:10","guid":{"rendered":"http:\/\/www.chemicool.com\/elements\/?page_id=417"},"modified":"2017-12-07T02:08:38","modified_gmt":"2017-12-07T07:08:38","slug":"tellurium","status":"publish","type":"page","link":"https:\/\/www.chemicool.com\/elements\/tellurium.html","title":{"rendered":"Tellurium 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\">52<\/div>\n<div class=\"clearT\"><\/div>\n<div class=\"elnamT\">Te<\/div>\n<div class=\"atweiT\"> 127.6<\/div>\n<\/div>\n<p>The chemical element tellurium is classed as a chalcogen and a metalloid. It was discovered in 1798 by Martin H. Klaproth.<\/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>  Tellurium is a chalcogen and 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>   127.60 <\/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> 450 <sup>o<\/sup>C, 723 K   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Boiling point:<\/td>\n<td>  990 <sup>o<\/sup>C, 1263 K     <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electrons:<\/td>\n<td>52<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Protons:<\/td>\n<td>52<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Neutrons in most abundant isotope:<\/td>\n<td>78<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron shells:<\/td>\n<td>   2,8,18,18,6   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron configuration:<\/td>\n<td>   [Kr] 4d<sup>10<\/sup> 5s<sup>2<\/sup>  5p<sup>4<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Density @ 20<sup>o<\/sup>C:<\/td>\n<td>  6.24 g\/cm<sup>3<\/sup>   <\/td>\n<\/tr>\n<\/table>\n<span class=\"collapseomatic \" id=\"id6a37f1e543cd8\"  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-id6a37f1e543cd8\" class=\"collapseomatic_content \">\n<table class=\"datatop\">\n<tr>\n<td class=\"elemglb\">Atomic volume:<\/td>\n<td>   20.5  cm<sup>3<\/sup>\/mol   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Structure:<\/td>\n<td>    parallel chains <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Hardness: <\/td>\n<td>   2.3 mohs <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Specific heat capacity<\/td>\n<td>  0.20 J g<sup>-1<\/sup> K<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of fusion<\/td>\n<td>  17.490  kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of atomization<\/td>\n<td> 197 kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of vaporization<\/td>\n<td>    52.550 kJ mol<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">1<sup>st<\/sup> ionization energy<\/td>\n<td> 869.2 kJ mol<sup>-1<\/sup>    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">2<sup>nd<\/sup> ionization energy<\/td>\n<td>   1794.6  kJ mol<sup>-1<\/sup>    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">3<sup>rd<\/sup> ionization energy<\/td>\n<td>    2697.7 kJ mol<sup>-1<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron affinity<\/td>\n<td>    190.16 kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Minimum oxidation number<\/td>\n<td>  -2    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Min. common oxidation no.<\/td>\n<td>  0   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Maximum oxidation number <\/td>\n<td> 6 <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Max. common oxidation no. <\/td>\n<td>  6  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Electronegativity (Pauling Scale) <\/td>\n<td> 2.1   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Polarizability volume <\/td>\n<td>   5.5 &Aring;<sup>3<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with air<\/td>\n<td>  mild, w\/ht &#8658;  TeO<sub>2<\/sub>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with 15 M HNO<sub>3<\/sub> <\/td>\n<td> mild , &#8658;  Te(IV)  <\/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>   none  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Oxide(s) <\/td>\n<td>  TeO (brown), TeO<sub>2<\/sub> (white), TeO<sub>3<\/sub> (orange\/yellow) <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Hydride(s) <\/td>\n<td>  TeH<sub>2<\/sub>  (hydrogen telluride) <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Chloride(s) <\/td>\n<td>   Te<sub>2<\/sub>Cl, TeCl<sub>2<\/sub>, Te<sub>3<\/sub>Cl<sub>2<\/sub>, Te<sub>4<\/sub>Cl<sub>16<\/sub> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Atomic radius <\/td>\n<td>  142 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> 90  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> 207  pm <\/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> 3 W m<sup>-1<\/sup> K<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Electrical conductivity <\/td>\n<td>  0.0002 x 10<sup>6<\/sup> S m<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Freezing\/Melting point:<\/td>\n<td> 450 <sup>o<\/sup>C, 723 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:\/\/chemicool.com\/elements\/images\/300-tellurium.jpg\" width=\"300\" height=\"163\" alt=\"Crystalline tellurium\" class=\"size-full\" \/><p class=\"wp-caption-text\">Crystalline tellurium. Image by Dschwen. <sup>(1)<\/sup><\/p><\/div>\n<div style=\"width: 310px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.chemicool.com\/elements\/images\/300-calaverite.jpg\" width=\"300\" height=\"227\" alt=\"Calaverite\" class=\"size-full\" \/><p class=\"wp-caption-text\">The mineral ore calaverite. Calaverite is also known as gold telluride, AuTe<sub>2<\/sub>. It is the mineral tellurium was discovered in. Image by Robert Lavinsky. <sup>(2)<\/sup><\/p><\/div>\n<\/div>\n<\/div>\n<p><a id=\"discovery\"><\/a><\/p>\n<h2>Discovery of Tellurium<\/h2>\n<div class=\"author\">Dr. Doug Stewart<\/div>\n<p>In the 1700s, scientists were confused by a substance found in various ores.<\/p>\n<p>Although they could not isolate the substance, the properties of the ores seemed to indicate that that the substance had both metallic and non-metallic properties. <\/p>\n<p>They called the new substance &#8216;aurum paradoxum&#8217; meaning <em>paradoxical\/illogical gold<\/em> or &#8216;metallum problematum&#8217; meaning <em>problem metal<\/em>.<\/p>\n<p>In 1782, Austro-Hungarian mineralogist Baron Franz Muller von Reichenstein purified a substance, which he believed to contain <a href=\"https:\/\/www.chemicool.com\/elements\/antimony.html\">antimony<\/a>, from a Transylvanian gold ore. (We now know this ore was actually gold telluride, AuTe<sub>2<\/sub>, often known as calaverite.)<\/p>\n<p>Muller came to believe that his initial thoughts were wrong and that he might be dealing with a new element. <sup>(3)<\/sup> <\/p>\n<p>He sent a small sample to Torbern Bergman in Uppsala, Sweden, who replied in April 1784, agreeing that the substance did not contain antimony. Bergman asked for more samples so that he could study the substance further, but he died in July of that year. <sup>(4)<\/sup><\/p>\n<p>Twelve years later, Muller sent a sample to Martin H. Klaproth in Berlin, who isolated the tellurium. In 1798, Klaproth publicly confirmed the existence of a new element in the sample sent to him by Muller. <\/p>\n<p>Klaproth named the new element tellurium. The name comes from the Latin word &#8216;tellus&#8217; meaning Earth. <\/p>\n<p>It took a further 34 years for the chemistry of tellurium to be investigated. <\/p>\n<p>In 1832, in Stockholm, Sweden, Jons Jacob Berzelius made a detailed study of the element and its compounds. He decided that tellurium was a metal, but belonged in the same group as the nonmetals sulfur and selenium due to the similarities of their compounds. <sup>(5)<\/sup> <\/p>\n<p>We now class tellurium as a metalloid because, as the confused scientists of the 1700s first noticed, it has properties that sit between those of metals and nonmetals. <\/p>\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<div style=\"width: 310px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.chemicool.com\/elements\/images\/300-tellurium-alloy-NIR-detector.jpg\" width=\"300\" height=\"163\" alt=\"photosensitive surface\" class=\"size-full\" \/><p class=\"wp-caption-text\">Hubble Telescope Wide Field Camera 3. The crystalline photosensitive surface of the camera&#8217;s near-infrared detector is composed of <a href=\"https:\/\/www.chemicool.com\/elements\/mercury.html\">mercury<\/a>, <a href=\"https:\/\/www.chemicool.com\/elements\/cadmium.html\"> cadmium<\/a> and tellurium (HgCdTe). (NASA)<\/p><\/div>\n<div style=\"width:300px;\">\n<strong>Tellurium&#8217;s Periodic Table Neighborhood<\/strong><br \/>\nTellurium is a metalloid. It sits in the periodic table on the boundary between metals and nonmetals. Its behavior also sits between that of metals and nonmetals.\n<\/div>\n<table class=\"navbar\">\n<tr>\n<td class=\"info\"><\/td>\n<td class=\"info\">Group 15<\/td>\n<td class=\"info\">Group 16<\/td>\n<td class=\"info\">Group 17<\/td>\n<\/tr>\n<tr>\n<td class=\"info\">Row 4<\/td>\n<td><a class=\"metalloid\" href=\"https:\/\/www.chemicool.com\/elements\/arsenic.html\" title=\"arsenic \"><sup>33<\/sup><br \/>As<\/a> <\/td>\n<td><a class=\"onm\" href=\"https:\/\/www.chemicool.com\/elements\/selenium.html\" title=\"selenium \"><sup>34<\/sup><br \/>Se<\/a> <\/td>\n<td><a class=\"halogens-liquid\" href=\"https:\/\/www.chemicool.com\/elements\/bromine.html\" title=\"bromine \"><sup>35<\/sup><br \/>Br<\/a> <\/td>\n<\/tr>\n<tr>\n<td class=\"info\">Row 5<\/td>\n<td><a class=\"metalloid\"  href=\"https:\/\/www.chemicool.com\/elements\/antimony.html\" title=\"antimony \"><sup>51<\/sup><br \/>Sb<\/a> <\/td>\n<td><a class=\"metalloid\"  href=\"https:\/\/www.chemicool.com\/elements\/tellurium.html\" title=\"tellurium \"><sup>52<\/sup><br \/>Te<\/a> <\/td>\n<td><a class=\"halogens\" href=\"https:\/\/www.chemicool.com\/elements\/iodine.html\" title=\"iodine \"><sup>53<\/sup><br \/>I<\/a> <\/td>\n<\/tr>\n<tr>\n<td class=\"info\">Row 6<\/td>\n<td><a class=\"ometals\" href=\"https:\/\/www.chemicool.com\/elements\/bismuth.html\" title=\"bismuth \"><sup>83<\/sup><br \/>Bi<\/a> <\/td>\n<td><a class=\"metalloid\" href=\"https:\/\/www.chemicool.com\/elements\/polonium.html\" title=\"polonium \"><sup>84<\/sup><br \/>Po<\/a> <\/td>\n<td><a class=\"halogens\" href=\"https:\/\/www.chemicool.com\/elements\/astatine.html\" title=\"astatine \"><sup>85<\/sup><br \/>At<\/a> <\/td>\n<\/tr>\n<\/table>\n<div style=\"line-height:15px;\">&nbsp;<\/div>\n<div style=\"width: 310px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.chemicool.com\/elements\/images\/300-cadmium-telluride-solar-panels.jpg\" width=\"300\" height=\"200\" alt=\"Cadmium Telluride Solar Panels\" class=\"size-full\" \/><p class=\"wp-caption-text\">Cadmium telluride (CaTe) is used as a thin film in solar panels, converting sunlight to electricity. These solar panels are more efficient than amorphous silicon alternatives. Image from NREL.<\/p><\/div>\n<\/div>\n<\/div>\n<\/div>\n<p><a id=\"appear\"><\/a><\/p>\n<h3>Appearance and Characteristics<\/h3>\n<p>\t<strong>Harmful effects:<\/strong> <\/p>\n<p>\t \tTellurium is very toxic and teratogenic (can cause harm to developing embryos). Exposure to as little as 0.01 mg\/m<sup>2<\/sup> or less in air leads to &#8220;tellurium breath&#8221;, which has a garlic-like odor.<\/p>\n<p>\t  <strong>Characteristics:<\/strong><\/p>\n<p>\t\t Tellurium is a rare, silvery-white, brittle, lustrous metalloid.<\/p>\n<p>\t\tIt burns in air with a greenish-blue flame and forms white tellurium dioxide (TeO<sub>2<\/sub>).<\/p>\n<p>When present in compounds, tellurium exists mostly in the oxidation state IV and VI.<\/p>\n<p>\t\tTellurium is a semiconductor material and is slightly photosensitive.<\/p>\n<p>\t\tIt forms many compounds corresponding to those of <a href=\"https:\/\/www.chemicool.com\/elements\/sulfur.html\">sulfur<\/a> and <a href=\"https:\/\/www.chemicool.com\/elements\/selenium.html\">selenium<\/a>, the elements above it in the periodic table. For example, it forms tellurides with other metals and tellurite (TeO<sub>3<\/sub><sup>2-<\/sup>) and tellurate (TeO<sub>4<\/sub><sup>2-<\/sup>) compounds. <\/p>\n<p>\t\tTellurium has radioactive isotopes and is the lightest element to exhibit alpha decay.<\/p>\n<p><a id=\"uses\"><\/a><\/p>\n<h2>Uses of Tellurium<\/h2>\n<p>\t\tTellurium is alloyed with <a href=\"https:\/\/www.chemicool.com\/elements\/copper.html\">copper<\/a> and stainless steel to make these metals more workable.<\/p>\n<p>\t\tIt is added at very low levels to <a href=\"https:\/\/www.chemicool.com\/elements\/lead.html\">lead<\/a> to decreases the corrosive action of sulfuric acid in batteries and to improve the lead&#8217;s strength and hardness.<\/p>\n<p>\t\tTellurium is used as a coloring agent in ceramics.<\/p>\n<p>\t\tTellurium is also used in the electronics industry, for example with <a href=\"https:\/\/www.chemicool.com\/elements\/cadmium.html\">cadmium<\/a> and <a href=\"https:\/\/www.chemicool.com\/elements\/mercury.html\">mercury<\/a> to form photosensitive semiconductors. Cadmium telluride (CdTe) is used as a thin film in solar panels to convert sunlight into electricity. CdTe panels have an efficiency rating of between 11 and 13 percent compared to amorphous silicon solar panels which have an efficiency of between 7 to 9 percent. <sup>(6)<\/sup><\/p>\n<p>\t\tIt is used in vulcanizing rubber and in catalysts for petroleum cracking and in blasting caps for explosives.<\/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>  1 part per billion by weight, 0.2 parts per billion by moles<\/p>\n<p>\t\t<span class=\"elemgl\">Abundance solar system:<\/span> <\/p>\n<p>\t\t\t\t<span class=\"elemgl\">Cost, pure:<\/span> $24 per 100g<\/p>\n<p>\t\t\t\t<span class=\"elemgl\">Cost, bulk:<\/span>   $0.44 per 100g<\/p>\n<p>\t\t<span class=\"elemgl\">Source:<\/span> Tellurium is sometimes found free in nature. More commonly, it is found combined with metals, such as in the minerals calaverite (gold telluride, AuTe<sub>2<\/sub>) and sylvanite (silver-gold telluride). Commercially, tellurium is obtained as a byproduct of electrolytic <a href=\"https:\/\/www.chemicool.com\/elements\/copper.html\">copper<\/a> refining. <\/p>\n<p>\t\t<span class=\"elemgl\">Isotopes:<\/span> Tellurium has 33 isotopes whose half-lives are known, with mass numbers 106 to 138.  Naturally occurring tellurium is a mixture of eight isotopes and they are found in the percentages shown: <sup>120<\/sup>Te (0.1%), <sup>122<\/sup>Te (2.6%), <sup>123<\/sup>Te (0.9%), <sup>124<\/sup>Te (4.8%), <sup>125<\/sup>Te (7.1%), <sup>126<\/sup>Te (19.0%), <sup>128<\/sup>Te (31.7%), and <sup>130<\/sup>Te (33.8%). <\/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>Image by <a rel=\"nofollow\" href=\"http:\/\/commons.wikimedia.org\/wiki\/User:Dschwen\">Dschwen<\/a><\/li>\n<li>Image by <a rel=\"nofollow\" href=\"http:\/\/commons.wikimedia.org\/wiki\/Commons:Robert_Lavinsky\">Rob Lavinski<\/a> \/ <a rel=\"nofollow\" href=\"http:\/\/www.irocks.com\/\">iRocks.com<\/a><\/li>\n<li> Mary Elvira Weeks, The Discovery of the Elements VI. Tellurium and Selenium, Journal of Chemical Education., March 1932, p474.<\/li>\n<li> Per Enghag, Encyclopedia of the Elements: Technical Data &#8211; History &#8211; Processing &#8211; Applications, 2008, John Wiley &#038; Sons, p1067<\/li>\n<li> B. Smith Hopkins, Chemistry of the Rarer Elements, 1923, D.C. Heath and Company, p327<\/li>\n<li> <a href=\"http:\/\/ocw.mit.edu\/courses\/materials-science-and-engineering\/3-003-principles-of-engineering-practice-spring-2010\/projects\/MIT3_003S10_project1B_sw1.pdf\">MIT OpenCourseWare, 3.003 Principles of Engineering Practice, 2010<\/a> (pdf).<\/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\/tellurium.html\"&gt;Tellurium&lt;\/a&gt;\r\n<\/pre>\n<p>or<\/p>\n<pre class='code'>\r\n&lt;a href=\"https:\/\/www.chemicool.com\/elements\/tellurium.html\"&gt;Tellurium 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\"Tellurium.\" Chemicool Periodic Table. Chemicool.com. 18 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\/tellurium.html&gt;.<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Data Zone | Discovery | Facts | Appearance &amp; Characteristics | Uses | Abundance &amp; Isotopes | References 52 Te 127.6 The chemical element tellurium is classed as a chalcogen and a metalloid. It was discovered in 1798 by Martin H. Klaproth. Data Zone Classification: Tellurium is a chalcogen and a metalloid Color: silvery Atomic [&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-417","1":"page","2":"type-page","3":"status-publish","5":"entry"},"_links":{"self":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/417","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=417"}],"version-history":[{"count":28,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/417\/revisions"}],"predecessor-version":[{"id":4308,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/417\/revisions\/4308"}],"wp:attachment":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/media?parent=417"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}