{"id":762,"date":"2012-06-03T08:28:01","date_gmt":"2012-06-03T08:28:01","guid":{"rendered":"http:\/\/www.chemicool.com\/elements\/?page_id=762"},"modified":"2017-12-07T02:07:25","modified_gmt":"2017-12-07T07:07:25","slug":"americium","status":"publish","type":"page","link":"https:\/\/www.chemicool.com\/elements\/americium.html","title":{"rendered":"Americium 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=\"rareT\">\n<div class=\"atnorT\">95<\/div>\n<div class=\"clearT\"><\/div>\n<div class=\"elnamT\">Am<\/div>\n<div class=\"atweiT\">(243)<\/div>\n<\/div>\n<p>The chemical element americium is classed as an an actinide metal. It was discovered in 1944 by Seaborg, James and Morgan.<\/p>\n<div style=\"clear:both;\"><\/div>\n<div class=\"adsense300\">\n<div class=\"adsense300spacer\">\n<div style=\"line-height:10px;\">\n<img decoding=\"async\" alt=\"\" src=\"\/\/www.chemicool.com\/ad.png\"\/>\n<\/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>   Americium is an actinide metal   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Color:<\/td>\n<td> silvery-white <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Atomic weight:<\/td>\n<td>   (243), no stable isotopes <\/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>  1176 <sup>o<\/sup>C, 1449 K  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Boiling point:<\/td>\n<td>   2607 <sup>o<\/sup>C, 2880 K     <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electrons:<\/td>\n<td>95<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Protons:<\/td>\n<td>95<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Neutrons in most abundant isotope:<\/td>\n<td>148<\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron shells:<\/td>\n<td>   2,8,18,32,25,8,2   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron configuration:<\/td>\n<td>   [Rn] 5f<sup>7<\/sup> 7s<sup>2<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Density @ 20<sup>o<\/sup>C:<\/td>\n<td> 13.67 g\/cm<sup>3<\/sup>   <\/td>\n<\/tr>\n<\/table>\n<span class=\"collapseomatic \" id=\"id6a26384260e2f\"  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-id6a26384260e2f\" class=\"collapseomatic_content \">\n<table class=\"datatop\">\n<tr>\n<td class=\"elemglb\">Atomic volume:<\/td>\n<td>   17.78 cm<sup>3<\/sup>\/mol   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Structure:<\/td>\n<td>  hcp: hexagonal close-packed <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Hardness: <\/td>\n<td>     mohs <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Specific heat capacity<\/td>\n<td> 0.11 J g<sup>-1<\/sup> K<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of fusion<\/td>\n<td>  14.40 kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of atomization<\/td>\n<td> 266 kJ mol<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Heat of vaporization<\/td>\n<td>   238.5 kJ mol<sup>-1<\/sup>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">1<sup>st<\/sup> ionization energy<\/td>\n<td>  578 kJ mol<sup>-1<\/sup>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">2<sup>nd<\/sup> ionization energy<\/td>\n<td>  &#8211;   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">3<sup>rd<\/sup> ionization energy<\/td>\n<td>   &#8211;   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Electron affinity<\/td>\n<td>  &#8211;  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Minimum oxidation number<\/td>\n<td>  0    <\/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>  3  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Electronegativity (Pauling Scale) <\/td>\n<td> 1.3   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Polarizability volume <\/td>\n<td>   23.3 &Aring;<sup>3<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with air<\/td>\n<td>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with 15 M HNO<sub>3<\/sub> <\/td>\n<td>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with 6 M HCl <\/td>\n<td>  <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Reaction with 6 M NaOH <\/td>\n<td>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Oxide(s) <\/td>\n<td>   AmO, AmO<sub>2<\/sub>, Am<sub>2<\/sub>O<sub>3<\/sub><\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Hydride(s) <\/td>\n<td>    AmH<sub>2<\/sub> AmH<sub>3<\/sub>   <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Chloride(s) <\/td>\n<td>   AmCl<sub>2<\/sub>, AmCl<sub>3<\/sub> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\">Atomic radius <\/td>\n<td>    173 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>  111.5 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> 10 W m<sup>-1<\/sup> K<sup>-1<\/sup> <\/td>\n<\/tr>\n<tr>\n<td class=\"elemglb\"> Electrical conductivity <\/td>\n<td>  0.7 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>  1176 <sup>o<\/sup>C, 1449 K  <\/td>\n<\/tr>\n<\/table>\n<\/div><\/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-americium-metal.jpg\" width=\"300\" height=\"158\" alt=\"Americium-241\" class=\"size-full\" \/><p class=\"wp-caption-text\">A small disc of americium-241 under the microscope. Image Ref.<sup>(3)<\/sup><\/p><\/div>\n<\/div>\n<\/div>\n<p><a id=\"discovery\"><\/a><\/p>\n<h2>Discovery of Americium<\/h2>\n<div class=\"author\">Dr. Doug Stewart<\/div>\n<p>   Americium  was the fourth synthetic transuranium element of the actinide series to be discovered.<\/p>\n<p>\t\t Americium-241 was first identified in 1944 by Seaborg, James and Morgan at the metallurgical laboratory at the University of Chicago. It was produced by the beta-particle decay of plutonium-241, which had been produced in a nuclear reactor by neutron bombardment of plutonium-239.<\/p>\n<p>\t\tThe researchers at first referred to americium as &#8220;pandemonium&#8221; owing to the difficulties they encountered trying to isolate it from another new element with which it was very closely associated,<br \/>\n\t\t curium &#8211; or &#8220;delirium&#8221; as it was first called.<\/p>\n<p>\t\tAmericium was first isolated as a pure compound by Burris Cunningham in 1945, at the University of Chicago.<\/p>\n<p>\t\tThe element was named after America, because it is located below <a href=\"\/elements\/europium.html\">Europium<\/a> (element 63) in the periodic table, which was named after Europe. <\/p>\n<div style=\"clear:both; line-height:20px;\">&nbsp;<\/div>\n<div class=\"adsense300\">\n<div class=\"adsense300spacer\">\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-americium-hydroxide.jpg\" width=\"300\" height=\"156\" alt=\"Americium hydroxide\" class=\"size-full\" \/><p class=\"wp-caption-text\">The triangle in the glass tube contains the world&#8217;s first sample of americium. (Photo credit: Berkeley Lab)<\/p><\/div>\n<p><iframe loading=\"lazy\" width=\"300\" height=\"169\" src=\"https:\/\/www.youtube.com\/embed\/AuUldLya3Wo?rel=0\" allowfullscreen><\/iframe><\/p>\n<div class=\"youtubecaption\">Americium-241 radiation emissions (preceded by Pitchblend ore) displayed in a cloud chamber.<\/div>\n<p><iframe loading=\"lazy\" width=\"300\" height=\"225\" src=\"https:\/\/www.youtube.com\/embed\/LxFXX0-hUYQ?rel=0\" allowfullscreen><\/iframe><\/p>\n<div class=\"youtubecaption\">Transuranium elements discovery and experiments. 1963 chemistry educational documentary narrated by Glenn Seaborg, Stanley Thompson and Albert Ghiorso.<\/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 Americium is harmful due to its radioactivity. <\/p>\n<p>\t  <strong>Characteristics:<\/strong><\/p>\n<p>\t\t Americium is a silvery-white highly radioactive metal that has a density similar to lead.<\/p>\n<p>\t\tIt tarnishes slowly in dry air at room temperature.<\/p>\n<p>\t\tIsotope <sup>241<\/sup>Am, the most common isotope,  decays to <sup>237<\/sup>Np, emitting alpha and gamma radiation<sup>(1)<\/sup>.<\/p>\n<p><a id=\"uses\"><\/a><\/p>\n<h2>Uses of Americium<\/h2>\n<p>\t\tIsotope <sup>241<\/sup>Am is used (in the form of americium dioxide) in very small amounts in &#8216;ionization chamber&#8217; smoke detectors. One gram of americium dioxide provides enough active material for more than three million household smoke detectors<sup>(2)<\/sup>.<\/p>\n<p>Americium is used as a portable source of gamma rays and alpha particles for use in medicine, science  and industry.<\/p>\n<p>It is also used as a target material in nuclear research to make even heavier elements.<\/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>  nil<\/p>\n<p>\t\t<span class=\"elemgl\">Abundance solar system:<\/span> negligible<\/p>\n<p>\t\t\t\t<span class=\"elemgl\">Cost, pure:<\/span>  $1500 per g<\/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> Americium is obtained as a by-product of <a href=\"https:\/\/www.chemicool.com\/elements\/plutonium.html\">plutonium<\/a> processing.<\/p>\n<p>\t\t<span class=\"elemgl\">Isotopes:<\/span> Americium has 14 isotopes whose half-lives are known, with mass numbers 232 to 247. Americium has no naturally occurring isotopes. Its longest lived isotopes are <sup>243<\/sup>Am, with a half-life of 7370 years, <sup>241<\/sup>Am with a half-life of 432.2 years and <sup>242<\/sup>Am with a half-life of 141 years.<\/p>\n<div style=\"clear:both;line-height:2px;\">&nbsp;<\/div>\n<div style=\"max-width:750px;\">\n<div style=\"line-height:10px;\">\n<img decoding=\"async\" alt=\"\" src=\"\/\/www.chemicool.com\/ad.png\"\/>\n<\/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>\n<\/div>\n<p><a id=\"refer\"><\/a><\/p>\n<h4>References<\/h4>\n<ol class=\"ref\">\n<li>James D. Navratil, Wallace W. Schulz, Glenn T. Seaborg., The Most Useful Actinide Isotope: Americium-241., Journal of Chemical Education. 67.1 (1990): p15-16. <\/li>\n<li><a href=\"http:\/\/www.world-nuclear.org\/info\/inf57.html\">Smoke Detectors and Americium<\/a>., World Nuclear Association. <\/li>\n<li>Photo: <a rel=\"nofollow\" href=\"http:\/\/en.wikipedia.org\/wiki\/User:Bionerd\">Bionerd<\/a><\/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\/americium.html\"&gt;Americium&lt;\/a&gt;\r\n<\/pre>\n<p>or<\/p>\n<pre class='code'>\r\n&lt;a href=\"https:\/\/www.chemicool.com\/elements\/americium.html\"&gt;Americium 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\"Americium.\" 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\/americium.html&gt;.<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Data Zone | Discovery | Facts | Appearance &amp; Characteristics | Uses | Abundance &amp; Isotopes | References 95 Am (243) The chemical element americium is classed as an an actinide metal. It was discovered in 1944 by Seaborg, James and Morgan. Data Zone Classification: Americium is an actinide metal Color: silvery-white Atomic weight: (243), [&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-762","1":"page","2":"type-page","3":"status-publish","5":"entry"},"_links":{"self":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/762","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=762"}],"version-history":[{"count":26,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/762\/revisions"}],"predecessor-version":[{"id":4366,"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/pages\/762\/revisions\/4366"}],"wp:attachment":[{"href":"https:\/\/www.chemicool.com\/elements\/wp-json\/wp\/v2\/media?parent=762"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}