{"id":205395,"date":"2025-03-24T12:00:49","date_gmt":"2025-03-24T12:00:49","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=205395"},"modified":"2025-03-24T12:00:51","modified_gmt":"2025-03-24T12:00:51","slug":"three-naturally-occurring-isotopes-exist-for-the-hypothetical-element-athenium","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/24\/three-naturally-occurring-isotopes-exist-for-the-hypothetical-element-athenium\/","title":{"rendered":"Three naturally occurring isotopes exist for the hypothetical element athenium"},"content":{"rendered":"\n<p>Three naturally occurring isotopes exist for the hypothetical element athenium. 2.50% of athenium atoms have a relative mass of 26.0 amu, 75.0% of athenium atoms have a relative mass of 27.0 amu, and 22.5% of athenium atoms have a relative mass of 28.0 amu. What is the atomic mass of athenium?<\/p>\n\n\n\n<p>A) 26.8 amu<\/p>\n\n\n\n<p>B) 27.0 amu<\/p>\n\n\n\n<p>C) 28.0 amu<\/p>\n\n\n\n<p>D) 27.2 amu<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p>To find the atomic mass of athenium, we need to calculate the weighted average of the masses of its isotopes. The weighted average takes into account both the mass of each isotope and its relative abundance. Here&#8217;s the step-by-step process:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 1: List the isotopes and their abundances<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Isotope 1:<\/strong> Mass = 26.0 amu, Abundance = 2.50% or 0.0250<\/li>\n\n\n\n<li><strong>Isotope 2:<\/strong> Mass = 27.0 amu, Abundance = 75.0% or 0.750<\/li>\n\n\n\n<li><strong>Isotope 3:<\/strong> Mass = 28.0 amu, Abundance = 22.5% or 0.225<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Step 2: Calculate the contribution of each isotope to the atomic mass<\/h3>\n\n\n\n<p>The contribution of each isotope to the atomic mass is found by multiplying the mass of the isotope by its fractional abundance.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>For Isotope 1:<br>[<br>26.0 \\, \\text{amu} \\times 0.0250 = 0.65 \\, \\text{amu}<br>]<\/li>\n\n\n\n<li>For Isotope 2:<br>[<br>27.0 \\, \\text{amu} \\times 0.750 = 20.25 \\, \\text{amu}<br>]<\/li>\n\n\n\n<li>For Isotope 3:<br>[<br>28.0 \\, \\text{amu} \\times 0.225 = 6.30 \\, \\text{amu}<br>]<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Step 3: Add the contributions to find the total atomic mass<\/h3>\n\n\n\n<p>Now, sum the contributions of each isotope to get the total atomic mass:<\/p>\n\n\n\n<p>[<br>0.65 + 20.25 + 6.30 = 27.20 \\, \\text{amu}<br>]<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 4: Conclusion<\/h3>\n\n\n\n<p>The atomic mass of athenium is <strong>27.2 amu<\/strong>.<\/p>\n\n\n\n<p>Thus, the correct answer is <strong>D) 27.2 amu<\/strong>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation<\/h3>\n\n\n\n<p>The atomic mass of an element is the weighted average mass of all its isotopes, accounting for both their individual masses and their relative abundances. Since 75% of athenium atoms have a mass of 27.0 amu, this isotope contributes the most to the atomic mass. Although the other two isotopes (with masses of 26.0 amu and 28.0 amu) also contribute, their lower abundances mean they have less influence on the final value. By calculating the weighted average, we find that the atomic mass of athenium is closest to 27.2 amu.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/03\/image-1294.png\" alt=\"\" class=\"wp-image-205396\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Three naturally occurring isotopes exist for the hypothetical element athenium. 2.50% of athenium atoms have a relative mass of 26.0 amu, 75.0% of athenium atoms have a relative mass of 27.0 amu, and 22.5% of athenium atoms have a relative mass of 28.0 amu. What is the atomic mass of athenium? A) 26.8 amu B) [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-205395","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/205395","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=205395"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/205395\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=205395"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=205395"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=205395"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}