{"id":224217,"date":"2025-06-02T19:20:31","date_gmt":"2025-06-02T19:20:31","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=224217"},"modified":"2025-06-02T19:20:33","modified_gmt":"2025-06-02T19:20:33","slug":"41-676-67-8-or-68-mass-no-of-mol-x-ram-2x68-refer-to-the-diagram-below-to-answer-question","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/02\/41-676-67-8-or-68-mass-no-of-mol-x-ram-2x68-refer-to-the-diagram-below-to-answer-question\/","title":{"rendered":"41.676 = 67.8 or 68 mass = No of mol x Ram = 2×68 Refer to the diagram below to answer Question"},"content":{"rendered":"\n
= 41.676 = 67.8 or 68 mass = No of mol x Ram = 2x68 Refer to the diagram below to answer Question 2. The diagram below illustrates that the mass of an atom of element X is equivalent to the total mass of 7 hydrogen atoms. H H H H X H H H<\/pre>\n\n\n\n
\"\"<\/figure>\n\n\n\n
The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n
Answer:<\/strong>
The relative atomic mass of element X is 7 atomic mass units (u)<\/strong>. On today\u2019s carbon-12 scale that corresponds to the element lithium (Li), A\u1d63 \u2248 6.94<\/strong>, the only naturally occurring element whose average atomic mass rounds to 7.<\/p>\n\n\n\n
\n\n\n\n
Explanation<\/strong>
A balance simply compares masses. In the diagram one pan holds a single atom of unknown element X, while the opposite pan holds seven separate hydrogen (H) atoms. Because the beam is shown perfectly level, the two pans exert equal gravitational forces; in other words, their masses are identical<\/strong>.<\/p>\n\n\n\n
Chemistry expresses individual-atom masses on the relative atomic-mass scale<\/strong>. On the historical hydrogen scale the mass of one H atom is assigned a value of 1. (In modern practice we use one-twelfth of a \u00b9\u00b2C atom as 1 u; because a hydrogen atom is 1.008 u on that scale, the two systems differ only very slightly for lightweight atoms.) When a single X atom balances seven hydrogen atoms, its mass must be seven times larger than that of a single H atom<\/strong>: m(X)=7\u00d7m(H)\u2005\u200a\u27f9\u2005\u200aAr(X)=7m(\\text{X}) = 7 \\times m(\\text{H}) \\;\\Longrightarrow\\; A_{r}(\\text{X}) = 7<\/p>\n\n\n\n
Relative atomic mass is a dimensionless ratio, so no units need be attached beyond the conventional \u201cu\u201d. Converting to the carbon-12 scale: Ar(X)\u22487\u00d71.008\u2009u=7.06\u2009uA_{r}(\\text{X}) \\approx 7 \\times 1.008 \\,\\text{u} = 7.06 \\,\\text{u}<\/p>\n\n\n\n
Consulting a periodic table, the lone element whose naturally weighted atomic mass is essentially 7 u is lithium<\/strong>. (Lithium\u2019s average of 6.94 u reflects its two stable isotopes, \u2076Li and \u2077Li, in a 7.6 : 92.4 mixture.) Therefore element X must be lithium.<\/p>\n\n\n\n
This simple comparison illustrates a key idea in atomic theory: although atoms are unimaginably small, their masses keep fixed ratios<\/strong> \u2014 a fact that underpins the law of definite proportions and stoichiometric calculations. Early chemists such as Dalton and Cannizzaro deduced entire atomic-weight tables by measuring how much of one substance balanced another, exactly like the schematic scale you see here. Even today, high-precision mass spectrometers perform a conceptually identical task, but with far greater sensitivity, establishing the relative masses of isotopes that define the modern periodic table.<\/p>\n\n\n\n
\"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"
= 41.676 = 67.8 or 68 mass = No of mol x Ram = 2×68 Refer to the diagram below to answer Question 2. The diagram below illustrates that the mass of an atom of element X is equivalent to the total mass of 7 hydrogen atoms. H H H H X H H H […]<\/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-224217","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/224217","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=224217"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/224217\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=224217"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=224217"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=224217"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}