{"id":149,"date":"2015-11-10T00:26:58","date_gmt":"2015-11-10T00:26:58","guid":{"rendered":"http:\/\/www.earth-site.co.uk\/Education\/?page_id=149"},"modified":"2024-02-05T16:54:40","modified_gmt":"2024-02-05T16:54:40","slug":"decay-chains","status":"publish","type":"post","link":"https:\/\/www.earth-site.co.uk\/Education\/decay-chains\/","title":{"rendered":"Decay Chains"},"content":{"rendered":"<div id=\"CenterPaneLayer\">\n<h2 class=\"style1 style7\">&nbsp;<\/h2>\n<blockquote>\n<blockquote>\n<p class=\"MsoNormal\" style=\"text-align:justify;\"><span style=\"line-height:115%; font-family:'Verdana','sans-serif'; font-size:13.5pt; \">Decay Chains is the name  given to the stages of radioactive decay of unstable isotopes or elements. Some radioactive  isotopes decay into stable isotopes directly but some unstable or radioactive  isotopes decay into other unstable isotopes many times before becoming stable  and these stages are explained in the &lsquo;decay chain&rsquo;. These decay chains can be  useful when radioactively dating samples by comparing the ratios of the  isotopes in the chain.<\/span><\/p>\n<p class=\"MsoNormal\"><span style=\"font-family:'Verdana','sans-serif'; font-size:13.5pt; \">&nbsp;<\/span><\/p>\n<p class=\"MsoNormal\"><span style=\"line-height:115%; font-family:'Verdana','sans-serif'; font-size:18.0pt; \">Decay Chain of Uranium-238<\/span><\/p>\n<p class=\"MsoNormal\" style=\"text-align:justify;\"><span style=\"font-family:'Verdana','sans-serif'; font-size:13.5pt; \">Below is the decay chain  of Uranium-238 which is the most common isotope on earth. The stages shown in  the table are the most likely outcome of radioactive decay naturally however at  some stages it is possible for some of the elements to succumb to either alpha  or beta decay which obviously changes the outcome. The possible variations and  their likely hood and are shown in the key below.<\/span><\/p>\n<p class=\"MsoNormal\" style=\"text-align:justify;\">&nbsp;<\/p>\n<p class=\"MsoNormal\" style=\"text-align:justify;\">&nbsp;<\/p>\n<table class=\"MsoTableGrid\" border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"635\" style=\"background:#C6D9F1;border-collapse:collapse;border:none;\">\n<tr>\n<td width=\"68\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><strong><span style=\"font-family:'Arial','sans-serif'; font-size:9.0pt; \">Stage<\/span><\/strong><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border:solid black 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><strong><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Symbol<\/span><\/strong><strong><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/strong><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border:solid black 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><strong><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Element<\/span><\/strong><strong><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/strong><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border:solid black 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><strong><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Radiation<\/span><\/strong><strong><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/strong><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border:solid black 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><strong><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Half-Life<\/span><\/strong><strong><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/strong><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border:solid black 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><strong><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Decay Product<\/span><\/strong><strong><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/strong><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">1<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">U-238<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Uranium-238<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">alpha<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">4,460,000,000 years<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Th-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>92<\/sup><span style=\"font-size:14.0pt; \">U<\/span><sub>238&nbsp; <\/sub><span style=\"font-size:14.0pt; \">=<\/span> <sup>2<\/sup><span style=\"font-size:14.0pt; \">He<\/span><sub>4 <\/sub><span style=\"font-size:14.0pt; \">+ <\/span><sup>90<\/sup><span style=\"font-size:14.0pt; \">Th<\/span><sub>234<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">2<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Th-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Thorium-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">beta <\/span><span style=\"font-size:9.0pt; \">(<\/span><span style=\"font-size:9.0pt; \">&beta;)<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">24.1 days<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Pa-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>90<\/sup><span style=\"font-size:14.0pt; \">Th<\/span><sub>234<\/sub> <span style=\"font-size:14.0pt; \">= <\/span><sup>91<\/sup><span style=\"font-size:14.0pt; \">Pa<\/span><sub>234<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>0<\/sup><span style=\"font-size:14.0pt; \">e<\/span><sub>-1<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-size:9.0pt; \"> (see #1)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">3<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Pa-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Protactinium-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">beta <\/span><span style=\"font-size:9.0pt; \">(<\/span><span style=\"font-size:9.0pt; \">&beta;)<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">1.17 minutes<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">U-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>91<\/sup><span style=\"font-size:14.0pt; \">Pa<\/span><sub>234<\/sub> <span style=\"font-size:14.0pt; \">= <\/span><sup>92<\/sup><span style=\"font-size:14.0pt; \">U<\/span><sub>234<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>0<\/sup><span style=\"font-size:14.0pt; \">e<\/span><sub>-1<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-size:9.0pt; \"> (see #1)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">4<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">U-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Uranium-234<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">alpha<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">247,000 years<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Th-230<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>92<\/sup><span style=\"font-size:14.0pt; \">U<\/span><sub>234<\/sub> <span style=\"font-size:14.0pt; \">= <\/span><sup>90<\/sup><span style=\"font-size:14.0pt; \">Th<\/span><sub>230<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>2<\/sup><span style=\"font-size:14.0pt; \">He<\/span><sub>4<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">5<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Th-230<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Thorium-230<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">alpha<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">80,000 years<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Ra-226<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>90<\/sup><span style=\"font-size:14.0pt; \">Th<\/span><sub>230 <\/sub><span style=\"font-size:14.0pt; \">= <\/span><sup>88<\/sup><span style=\"font-size:14.0pt; \">Ra<\/span><sub>226<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>2<\/sup><span style=\"font-size:14.0pt; \">He<\/span><sub>4<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">6<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Ra-226<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Radium-226<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">alpha<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">1,602 years<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Rn-222<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>88<\/sup><span style=\"font-size:14.0pt; \">Ra<\/span><sub>226 <\/sub><span style=\"font-size:14.0pt; \">= <\/span><sup>86<\/sup><span style=\"font-size:14.0pt; \">Ra<\/span><sub>222<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>2<\/sup><span style=\"font-size:14.0pt; \">He<\/span><sub>4<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">7<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Rn-222<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Radon-222<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">alpha<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">3.82 days<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Po-218<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>86<\/sup><span style=\"font-size:14.0pt; \">Ra<\/span><sub>222 <\/sub><span style=\"font-size:14.0pt; \">= <\/span><sup>84<\/sup><span style=\"font-size:14.0pt; \">Po<\/span><sub>218<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>2<\/sup><span style=\"font-size:14.0pt; \">He<\/span><sub>4<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">8<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Po-218<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Polonium-218<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">alpha<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">3.05 minutes<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Pb-214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>84<\/sup><span style=\"font-size:14.0pt; \">Po<\/span><sub>218 <\/sub><span style=\"font-size:14.0pt; \">= <\/span><sup>82<\/sup><span style=\"font-size:14.0pt; \">Pb<\/span><sub>214<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>2<\/sup><span style=\"font-size:14.0pt; \">He<\/span><sub>4<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-size:9.0pt; \"> (see #2)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">9<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Pb-214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Lead-214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">beta <\/span><span style=\"font-size:9.0pt; \">(<\/span><span style=\"font-size:9.0pt; \">&beta;) <\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">27 minutes<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Bi-214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>82<\/sup><span style=\"font-size:14.0pt; \">Pb<\/span><sub>214<\/sub> <span style=\"font-size:14.0pt; \">= <\/span><sup>83<\/sup><span style=\"font-size:14.0pt; \">Bi<\/span><sub>214<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>0<\/sup><span style=\"font-size:14.0pt; \">e<\/span><sub>-1<\/sub><span style=\"font-size:14.0pt; \">) <\/span><span style=\"font-size:9.0pt; \">(see #1)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">10<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Bi-214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Bismuth-214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">beta <\/span><span style=\"font-size:9.0pt; \">(<\/span><span style=\"font-size:9.0pt; \">&beta;)<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">19.7 minutes<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Po -214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>83<\/sup><span style=\"font-size:14.0pt; \">Bi<\/span><sub>214<\/sub> <span style=\"font-size:14.0pt; \">= <\/span><sup>84<\/sup><span style=\"font-size:14.0pt; \">Po<\/span><sub>214<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>0<\/sup><span style=\"font-size:14.0pt; \">e<\/span><sub>-1<\/sub><span style=\"font-size:14.0pt; \">) <\/span><span style=\"font-size:9.0pt; \">(see #1 + #3)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">11<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Po-214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Polonium-214<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">alpha<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">1 microsecond<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Pb-210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>84<\/sup><span style=\"font-size:14.0pt; \">Po<\/span><sub>214<\/sub> <sub>&nbsp;<\/sub><span style=\"font-size:14.0pt; \">= <\/span><sup>82<\/sup><span style=\"font-size:14.0pt; \">Pb<\/span><sub>210<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>2<\/sup><span style=\"font-size:14.0pt; \">He<\/span><sub>4<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">12<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Pb-210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Lead-210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">beta <\/span><span style=\"font-size:9.0pt; \">(<\/span><span style=\"font-size:9.0pt; \">&beta;)<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">22.3 years<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Bi-210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>82<\/sup><span style=\"font-size:14.0pt; \">Pb<\/span><sub>210<\/sub> <span style=\"font-size:14.0pt; \">= <\/span><sup>83<\/sup><span style=\"font-size:14.0pt; \">Bi<\/span><sub>210<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>0<\/sup><span style=\"font-size:14.0pt; \">e<\/span><sub>-1<\/sub><span style=\"font-size:14.0pt; \">) <\/span><span style=\"font-size:9.0pt; \">(see #1)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">13<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Bi-210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Bismuth-210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">beta <\/span><span style=\"font-size:9.0pt; \">(<\/span><span style=\"font-size:9.0pt; \">&beta;)<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">5.01 days<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Po -210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>83<\/sup><span style=\"font-size:14.0pt; \">Bi<\/span><sub>210<\/sub> <span style=\"font-size:14.0pt; \">= <\/span><sup>84<\/sup><span style=\"font-size:14.0pt; \">Po<\/span><sub>210<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>0<\/sup><span style=\"font-size:14.0pt; \">e<\/span><sub>-1<\/sub><span style=\"font-size:14.0pt; \">) <\/span><span style=\"font-size:9.0pt; \">(see #1 + #4)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" rowspan=\"2\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:14.0pt; \">14<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Po-210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Polonium-210<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">alpha<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">138.4 days<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Pb-206<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"567\" colspan=\"5\" style=\"width:12.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;background:#DBE5F1;padding:0cm 5.4pt 0cm 5.4pt;\" bgcolor=\"#DBE5F1\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-size:14.0pt; \">(<\/span><sup>84<\/sup><span style=\"font-size:14.0pt; \">Po<\/span><sub>210<\/sub> <sub>&nbsp;<\/sub><span style=\"font-size:14.0pt; \">= <\/span><sup>82<\/sup><span style=\"font-size:14.0pt; \">Pb<\/span><sub>206<\/sub> <span style=\"font-size:14.0pt; \">+ <\/span><sup>2<\/sup><span style=\"font-size:14.0pt; \">He<\/span><sub>4<\/sub><span style=\"font-size:14.0pt; \">)<\/span><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"68\" valign=\"top\" style=\"width:40.85pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:9.0pt; \">Stable Isotope<\/span><\/p>\n<\/td>\n<td width=\"83\" style=\"width:49.6pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Pb-206<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"154\" style=\"width:92.15pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">Lead-206<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"106\" style=\"width:63.8pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">&#8211;<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"130\" style=\"width:77.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">&#8211;<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<td width=\"95\" style=\"width:2.0cm;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" align=\"center\" style=\"margin-bottom:.0001pt;text-align:center;line-height:normal;\"><span style=\"font-family:'Arial','sans-serif'; font-size:10.0pt; \">&#8211;<\/span><span style=\"font-size:12.0pt; color:navy; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<\/table>\n<p class=\"MsoNormal\">&nbsp;<\/p>\n<p class=\"MsoNormal\">&nbsp;<\/p>\n<p class=\"MsoNormal\"><span style=\"line-height:115%; font-family:'Verdana','sans-serif'; font-size:18.0pt; \">Key<\/span><\/p>\n<p class=\"MsoNormal\">&nbsp;<\/p>\n<table class=\"MsoTableGrid\" border=\"1\" cellspacing=\"0\" cellpadding=\"0\" style=\"border-collapse:collapse;border:none;\">\n<tr>\n<td width=\"54\" valign=\"top\" style=\"width:32.45pt;border:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; \">Key<\/span><\/p>\n<\/td>\n<td style=\"border:none;border-bottom:solid black 1.0pt;padding:0cm 0cm 0cm 0cm;\" width=\"628\"><\/td>\n<\/tr>\n<tr>\n<td width=\"54\" valign=\"top\" style=\"width:32.45pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; \"># 1<\/span><\/p>\n<\/td>\n<td width=\"628\" valign=\"top\" style=\"width:376.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">Neutron    is converted into proton by beta (<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">&beta;&minus;) decay    and emits an electron.<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"54\" valign=\"top\" style=\"width:32.45pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; \"># 2<\/span><\/p>\n<\/td>\n<td width=\"628\" valign=\"top\" style=\"width:376.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p align=\"justify\" class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">99.98% of the time &nbsp;Polonium-218 will    decay by alpha decay to become lead-214 but the remaining 0.02% of the time    it will decay with beta radiation and become Astatine-218 (same half life of <\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">3.05 minutes<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">. Astatine-218 in 99.9% of the time will decay    by alpha radiation to become Bismuth-214 (half life of 3.10mins) and continue    from stage 13 on table. <\/span><\/p>\n<p align=\"justify\" class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">The other 0.1% of the time Astatine will succumb    to beta <\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">(<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">&beta;&minus;) decay and become Radon-218 (half life of 1.5 seconds).    The Radon-218 then succumbs to alpha decay and becomes Polonium-214 (half    life of 35 mille-seconds) which continues from stage 11 on table.<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"54\" valign=\"top\" style=\"width:32.45pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; \"># 3<\/span><\/p>\n<\/td>\n<td width=\"628\" valign=\"top\" style=\"width:376.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p align=\"justify\" class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">99.979% of the time Bismuth-214 will decay by    beta<sup>&#8211;<\/sup> decay to become Polonium-214 but the remaining 0.0211% of    the time it will decay with alpha radiation and become Thallium-210 (same    half life of 19.7 minutes). In this instance Thallium-210 will then decay by <\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">(<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">&beta;&minus;) radiation to become Lead-210 and continue to    stage 12 on table.<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"54\" valign=\"top\" style=\"width:32.45pt;border:solid black 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; \"># 4<\/span><\/p>\n<\/td>\n<td width=\"628\" valign=\"top\" style=\"width:376.95pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;\">\n<p align=\"justify\" class=\"MsoNormal\" style=\"margin-bottom:.0001pt;line-height:normal;\"><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">99.99987%    of the time &nbsp;Bismuth-210 will decay by beta<sup>&#8211;<\/sup> decay to become Polonium-210 but the remaining 0.00013% of the time it will    decay with alpha radiation and become Thallium-206 (same half life of <\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">5.01 days<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">). In this instance Thallium-206 will then decay    by <\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">(<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \">&beta;&minus;) radiation to become Lead-206 (half life of 4.199    minutes) which is the final stable isotope of Uranium-238<\/span><span style=\"font-family:'Arial Narrow','sans-serif'; font-size:10.0pt; \"> <\/span><\/p>\n<\/td>\n<\/tr>\n<\/table>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<\/blockquote>\n<\/blockquote>\n<blockquote><p>&nbsp;<\/p><\/blockquote>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp; Decay Chains is the name given to the stages of radioactive decay of unstable isotopes or elements. Some radioactive [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":5882,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_edit_last":["1"],"_edit_lock":["1707153067:1"],"_wp_page_template":["default"],"ttr_page_title_checkbox":["true"],"ttr_page_foot_checkbox":["true"],"ttr_header_size_select":["None"],"ttr_background_repeat_enable_checkbox":["true"],"ttr_change_header_image_text":[""],"ttr_background_size_select":["None"],"ttr_header_repeat_enable_checkbox":["true"],"ttr_custom_style_text":[""],"_yoast_wpseo_focuskw":["Decay Chains"],"_yoast_wpseo_metadesc":["Decay chains are the stages of radioactive decay of unstable isotopes or elements."],"_yoast_wpseo_linkdex":["44"],"ampforwp-amp-on-off":["default"],"_thumbnail_id":["5882"],"_yoast_wpseo_primary_category":["147"],"_yoast_wpseo_estimated-reading-time-minutes":["1"],"_yoast_wpseo_wordproof_timestamp":[""],"rank_math_primary_category":["147"],"rank_math_description":["Decay chains are the stages of radioactive decay of unstable isotopes or elements."],"rank_math_focus_keyword":["Decay Chains"],"rank_math_news_sitemap_robots":["index"],"rank_math_robots":["a:1:{i:0;s:5:\"index\";}"],"rank_math_seo_score":["60"],"_wds_opengraph":["a:3:{s:5:\"title\";s:0:\"\";s:11:\"description\";s:0:\"\";s:6:\"images\";a:1:{i:0;s:0:\"\";}}"],"_wds_twitter":["a:3:{s:5:\"title\";s:0:\"\";s:11:\"description\";s:0:\"\";s:6:\"images\";a:1:{i:0;s:0:\"\";}}"],"_wds_focus-keywords":["Decay Chains"],"_wds_title":[""],"_wds_metadesc":["Decay chains are the stages of radioactive decay of unstable isotopes or elements."],"_wds_meta-robots-adv":[""],"_wds_meta-robots-nofollow":[""],"_wds_canonical":[""],"_et_dynamic_cached_shortcodes":["a:0:{}"],"_et_dynamic_cached_attributes":["a:0:{}"]},"categories":[147],"tags":[],"class_list":["post-149","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-radioactivity"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.2 - 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