{"id":336,"date":"2012-05-24T06:46:49","date_gmt":"2012-05-24T06:46:49","guid":{"rendered":"http:\/\/www.chemicool.com\/elements\/?page_id=336"},"modified":"2017-12-07T02:07:25","modified_gmt":"2017-12-07T07:07:25","slug":"arsenic","status":"publish","type":"page","link":"https:\/\/www.chemicool.com\/elements\/arsenic.html","title":{"rendered":"Arsenic 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\">33<\/div>\n<div class=\"clearT\"><\/div>\n<div class=\"elnamT\">As<\/div>\n<div class=\"atweiT\">74.92<\/div>\n<\/div>\n<p>The chemical element arsenic is classed as a metalloid. It has been known since ancient times. Its discoverer and discovery date are unknown.<\/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>   Arsenic is a metalloid  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Color:<\/td>\n<td>  gray  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Atomic weight:<\/td>\n<td>  74.9216 <\/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> 817 <sup>o<\/sup>C, 1090 K   <\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\">Note: At normal atmospheric pressure arsenic does not melt when heated, it sublimes. i.e. when heated, arsenic undergoes a phase change directly from solid to gas.<br \/>\n\t\t The melting point quoted above is for gray arsenic under a pressure of 28 atmospheres.<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Boiling point:<\/td>\n<td>  603 <sup>o<\/sup>C, 876 K    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electrons:<\/td>\n<td>33<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Protons:<\/td>\n<td>33<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Neutrons in most abundant isotope:<\/td>\n<td>42<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron shells:<\/td>\n<td>  2,8,18,5    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron configuration:<\/td>\n<td>  [Ar] 3d<sup>10<\/sup> 4s<sup>2<\/sup> 4p<sup>3<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Density @ 20<sup>o<\/sup>C:<\/td>\n<td>  5.776 g\/cm<sup>3<\/sup>   <\/td>\n<\/tr>\n<\/table>\n<span class=\"collapseomatic \" id=\"id6a20bc196fe80\"  tabindex=\"0\" title=\"Show more, including: Heats, Energies, Oxidation, Reactions,&lt;br \/&gt; Compounds, Radii, Conductivities\"    >Show more, including: Heats, Energies, Oxidation, Reactions,<br \/> Compounds, Radii, Conductivities<\/span><div id=\"target-id6a20bc196fe80\" class=\"collapseomatic_content \">\n<table class=\"datatop\">\n<tr>\n<td class=\"elemglb\">Atomic volume:<\/td>\n<td>  12.97 cm<sup>3<\/sup>\/mol  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Structure:<\/td>\n<td>   rhombohedral; layers of 6-member rings <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Hardness: <\/td>\n<td>    3.5 mohs  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Specific heat capacity<\/td>\n<td>  0.33 J g<sup>-1<\/sup> K<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of fusion<\/td>\n<td> 24.44 kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of atomization<\/td>\n<td> 303 kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of vaporization<\/td>\n<td>   32.4 kJ mol<sup>-1<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">1<sup>st<\/sup> ionization energy<\/td>\n<td>  946.5 kJ mol<sup>-1<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">2<sup>nd<\/sup> ionization energy<\/td>\n<td>   1797.8 kJ mol<sup>-1<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">3<sup>rd<\/sup> ionization energy<\/td>\n<td>   2735.4 kJ mol<sup>-1<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron affinity<\/td>\n<td>    78 kJ mol<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Minimum oxidation number<\/td>\n<td>  -3    <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Min. common oxidation no.<\/td>\n<td>  -3   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Maximum oxidation number <\/td>\n<td> 5 <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Max. common oxidation no. <\/td>\n<td>  5  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Electronegativity (Pauling Scale) <\/td>\n<td> 2.18   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Polarizability volume <\/td>\n<td>    4.3 &Aring;<sup>3<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with air<\/td>\n<td>  mild, w\/ht &#8658; As<sub>4<\/sub>O<sub>6<\/sub>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with 15 M HNO<sub>3<\/sub> <\/td>\n<td>   mild, w\/ht &#8658; H<sub>3<\/sub>AsO<sub>4<\/sub>, NO<sub>x<\/sub>    <\/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>  As<sub>2<\/sub>O<sub>3<\/sub> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Hydride(s) <\/td>\n<td>   AsH<sub>3<\/sub>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Chloride(s) <\/td>\n<td>   AsCl<sub>3<\/sub> AsCl<sub>5<\/sub>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Atomic radius <\/td>\n<td>  115 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> 72 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\"> Thermal conductivity <\/td>\n<td> 50.2 W m<sup>-1<\/sup> K<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Electrical conductivity <\/td>\n<td>   3.85 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> 817 <sup>o<\/sup>C, 1090 K   <\/td>\n<\/tr>\n<\/table>\n<\/div>\n<\/div>\n<\/div>\n<p><a id=\"discovery\"><\/a><\/p>\n<h2>Discovery of Arsenic<\/h2>\n<div class=\"author\">Dr. Doug Stewart<\/div>\n<p>   Arsenic has been known since antiquity in its sulfide compound.<\/p>\n<p>\t\t Greek philosopher Aristotle, in the fourth century BC, refers to &#8220;sandarach&#8221; renamed arhenicum by his student Theophrastus of Eresos.<\/p>\n<p>\t\t Greek historian Olympiodorus of Thebes (5th century AD) roasted arsenic sulfide and obtained white arsenic (As<sub>2<\/sub>O<sub>3<\/sub>).<\/p>\n<p>\t\t Albertus Magnus (1193-1280), a German philosopher and theologian, was the first to state that arsenic has a metal-like nature. In De Mineralibus he described how the metal could be obtained by heating orpiment (As<sub>2<\/sub>S<sub>3<\/sub>) with soap.<\/p>\n<p>\t\t\tTwo methods of preparing arsenic were published by German pharmacist Johann Schroeder in 1649.<\/p>\n<p>The element name is believed to come from the Greek word &#8216;arsenikos&#8217; meaning potent.<\/p>\n<p>The image below shows a bottle of arsenious acid \u2013 a poison.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.chemicool.com\/elements\/images\/300-arsenious-acid.jpg\" width=\"300\" height=\"155\" alt=\"poison\" class=\"aligncenter size-full\" \/><\/p>\n<div style=\"clear: both; line-height: 20px;\"><\/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=\"225\" src=\"https:\/\/www.youtube.com\/embed\/lGr1a2h_AIQ\" allowfullscreen><\/iframe><\/p>\n<div class=\"youtubecaption\">3d model of arsenic (III) oxide, As<sub>2<\/sub>O<sub>3<\/sub>. Sometimes called white arsenic, it is colorless, tasteless and was a common poison used by criminals before the development of forensic science.\n<\/div>\n<div style=\"width: 310px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full\" src=\"https:\/\/www.chemicool.com\/elements\/images\/300-arsenical-poison.png\" alt=\"An old government warning poster.\" width=\"300\" height=\"354\" \/><p class=\"wp-caption-text\">An old government warning poster.<\/p><\/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 \tArsenic is immediately dangerous to life or health at 5 mg m<sup>-3<\/sup>.<\/p>\n<p>\t\t Our bodies do not readily absorb the element itself, hence pure arsenic is much less dangerous than As<sup>(III)<\/sup> compounds such as AsH<sub>3<\/sub> and As<sub>2<\/sub>O<sub>3<\/sub> which are absorbed easily and are carcinogenic with high toxicity.\t <\/p>\n<p>\t  <strong>Characteristics:<\/strong><\/p>\n<p>\t\t Arsenic occurs in three distinct solid forms. <\/p>\n<p>\t\tGray arsenic is the most common. It has a metallic sheen and conducts electricity. <\/p>\n<p>\t\tYellow arsenic is metastable, is a poor electrical conductor and does not have a metallic sheen. It is prepared by cooling gray arsenic vapor in liquid air. It reverts to gray arsenic at room temperature. <\/p>\n<p>\t\tBlack arsenic can be prepared by cooling arsenic vapor at 100 <sup>o<\/sup>C &#8211; 200 <sup>o<\/sup>C. It is glassy, brittle and a poor electrical conductor. <\/p>\n<p><a id=\"uses\"><\/a><\/p>\n<h2>Uses of Arsenic<\/h2>\n<p>\t\tAs a result of its toxicity, arsenic compounds are used in wood preservation and insecticides.<\/p>\n<p>    Gallium arsenide (GaAs) is a semiconductor used in laser diodes and LEDs.<\/p>\n<p>\t\tSmall amounts of arsenic (less than two percent) can be used in lead alloys for ammunition.<\/p>\n<p>\t\tDespite its potential toxicity, arsenic is also an essential element, necessary to our physiology. A level of 0.00001% is needed for growth and for a healthy nervous system.<\/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>  1.8 parts per million by weight, 0.5 parts per million by moles<\/p>\n<p>\t\t<span class=\"elemgl\">Abundance solar system:<\/span>  12 parts per billion by weight, 0.21 parts per billion by moles<\/p>\n<p>\t\t\t\t<span class=\"elemgl\">Cost, pure:<\/span> $320 per 100g<\/p>\n<p>\t\t\t\t<span class=\"elemgl\">Cost, bulk:<\/span>  $ per 100g<\/p>\n<p>\t\t<span class=\"elemgl\">Source:<\/span> Most arsenic is obtained as a by-product of processing gold, silver, <a href=\"https:\/\/www.chemicool.com\/elements\/copper.html\">copper<\/a>, and other metal ores.<\/p>\n<p>\t\t<span class=\"elemgl\">Isotopes:<\/span> Arsenic has 23 isotopes whose half-lives are known, with mass numbers 65 to 87. Of these, only one is stable: <sup>75<\/sup>As.<\/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<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\/arsenic.html\"&gt;Arsenic&lt;\/a&gt;\r\n<\/pre>\n<p>or<\/p>\n<pre class='code'>\r\n&lt;a href=\"https:\/\/www.chemicool.com\/elements\/arsenic.html\"&gt;Arsenic 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\"Arsenic.\" Chemicool Periodic Table. Chemicool.com. 15 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\/arsenic.html&gt;.<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Data Zone | Discovery | Facts | Appearance &amp; Characteristics | Uses | Abundance &amp; Isotopes | References 33 As 74.92 The chemical element arsenic is classed as a metalloid. It has been known since ancient times. Its discoverer and discovery date are unknown. Data Zone Classification: Arsenic is a metalloid Color: gray Atomic weight: [&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-336","1":"page","2":"type-page","3":"status-publish","5":"entry"},"_links":{"self":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/336","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=336"}],"version-history":[{"count":26,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/336\/revisions"}],"predecessor-version":[{"id":4369,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/336\/revisions\/4369"}],"wp:attachment":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/media?parent=336"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}