Atomic Weight of Tin | Commission on Isotopic Abundances and Atomic Weights

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"><head> <title>Atomic Weight of Tin | Commission on Isotopic Abundances and Atomic Weights</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <link rel="stylesheet" type="text/css" media="all" href="stylesheet.css"><link rel="shortcut icon" href="favicon.ico" /> <link href="css/theme.blue.css" rel="stylesheet" type="text/css"/> <script type="text/javascript" src="js/jquery-1.11.1.min.js"></script> <script type="text/javascript" src="js/jquery.tablesorter.js"></script> <script type="text/javascript" src="js/jquery.tablesorter.min.js"></script> <script type="text/javascript" src="js/jquery.tablesorter.widgets.js"></script> <script language="JavaScript" type="text/javascript"> $(function() { $("#mytable").tablesorter({theme:'blue',headers:{3:{sorter:'brace'},4:{sorter:false}},widgets:['zebra'],widthFixed:true}); }); </script> <script type="text/javascript"> var _gaq = _gaq || []; _gaq.push(['_setAccount', 'UA-37565923-4']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); </script> </head> <body> <div id="pagewidth"> <div id="header-top" class="clearfix">  <div id="support-navigation"> <ul></ul> </div>   <div id="logo-top"> <a href="http://www.ciaaw.org"><img src="images/ciaaw.png" alt="Logo of the Atomic Weights Commission"></a> <a href="http://www.iupac.org" target="_blank"><img src="images/iupac.png" class="xx" alt="Logo of the International Union of Pure and Applied Chemistry"></a> </div>   <div id="main-navigation"> <ul> <li><a href="index.htm">Home</a></li> <li><a href="atomic-weights.htm">Atomic Weights</a></li> <li><a href="isotopic-abundances.htm">Isotopic Abundances</a></li> <li><a href="reference-materials.htm">Reference Materials</a></li> <li><a href="commission.htm">The Commission</a></li> <li><a href="info.htm">FAQ's</a></li> </ul> </div>  </div id="header-top">  <div id="breadcrumb"> <ul> <li><a href="index.htm">Other elements</a></li> </ul></div> <div id="content"> <div id="main-content"> <h1>Tin</h1><p><table id="mytable" class="tablesorter"><thead><tr><th>Isotope</th><th>Atomic mass (Da)</th><th>Isotopic abundance (amount fraction)</th></tr></thead> <tbody> <tr><td><sup>112</sup>Sn </td><td>111.904 825(2)</td><td>0.0097(1)</td></tr> <tr><td><sup>114</sup>Sn </td><td>113.902 7801(2)</td><td>0.0066(1)</td></tr> <tr><td><sup>115</sup>Sn </td><td>114.903 3447(1)</td><td>0.0034(1)</td></tr> <tr><td><sup>116</sup>Sn </td><td>115.901 7428(6)</td><td>0.1454(9)</td></tr> <tr><td><sup>117</sup>Sn </td><td>116.902 954(3)</td><td>0.0768(7)</td></tr> <tr><td><sup>118</sup>Sn </td><td>117.901 607(3)</td><td>0.2422(9)</td></tr> <tr><td><sup>119</sup>Sn </td><td>118.903 311(5)</td><td>0.0859(4)</td></tr> <tr><td><sup>120</sup>Sn </td><td>119.902 202(6)</td><td>0.3258(9)</td></tr> <tr><td><sup>122</sup>Sn </td><td>121.903 44(2)</td><td>0.0463(3)</td></tr> <tr><td><sup>124</sup>Sn </td><td>123.905 277(7)</td><td>0.0579(5)</td></tr> </tbody></table><br> <p> In its 1961 report, the Commission recommended <i>A</i><sub>r</sub>(Sn) = 118.69 based on chemical-ratio determinations. From these measurements, with current values of the atomic weights of the other elements involved, the following atomic weights for Sn are derived: <i>A</i><sub>r</sub>(Sn) = 118.686, 118.691, and 118.701. The Commission was also aware that three mass-spectrometric determinations had been made that yield slightly higher atomic-weight values. </p><p> Tin has ten stable isotopes, the largest number of all elements. Because of this, the isotopic composition measurements involve an unusually large number of experimentally determined ratios, each subject to uncertainty. In 1969, the Commission assessed <i>A</i><sub>r</sub>(Sn) = 118.69(3) therefore preferring the chemically determined atomic-weight values. This viewpoint was reaffirmed until 1983 when the Commission was able to consider the first calibrated mass-spectrometric measurement, which reported <i>A</i><sub>r</sub>(Sn) = 118.7099(22) and demonstrated good agreement with many previous isotope-abundance measurements (after correcting those uncalibrated measurements for isotope fractionation). In 1983 the Commission changed the basis for the standard atomic weight of tin to mass spectrometry and the value to <i>A</i><sub>r</sub>(Sn) = 118.710(7). </p><p> The "g" annotation arises from the presence of naturally occurring fission products found in fossil reactors at Gabon, southwest Africa. </p> <h9><font color=red>SOURCE</font>  <a href="publications.htm#P3">Atomic weights of the elements: Review 2000</a> by John R de Laeter et al. <i>Pure Appl. Chem.</i> 2003 (75) 683-800<br>© IUPAC 2003</h9> </div>  <div id="support-content"> <img src="images/p-table/Sn.png"><p class="credit">CIAAW</p> <p class="caption"><strong>Tin</strong><br> <i>A</i><sub>r</sub>(Sn) = 118.710(7) since 1983<br><br> The name derives from the Anglo-Saxon <i>tin</i> of unknown origin. The symbol Sn is derived from Latin <i>stannum</i> for alloys containing lead. The element was known in prehistoric times. </p> </div id="support-content">  </div id="content">  <div id="push"></div></div id="pagewidth">  <div id="footer"> <img src="images/logo.png"><br><br> <a href="privacy.htm">Privacy policy</a>  |  <a href="impressum.htm">Impressum</a>  |  <a href="members.htm">Contact</a>  |  © CIAAW, 2007-2015 <br> </div>  </body></html>

CINXE.COM

Atomic Weight of Tin | Commission on Isotopic Abundances and Atomic Weights