If the atomic number is 18, then<\/p>\n\n\n\n
\u00b7 there are seven electrons in the outermost energy level.<\/p>\n\n\n\n
\u00b7 the atom has eighteen electrons in the nucleus.<\/p>\n\n\n\n
\u00b7 the outermost energy level is full.<\/p>\n\n\n\n
\u00b7 All of the above are true.<\/p>\n\n\n\n
The Correct Answer and Explanation is :<\/strong><\/mark><\/p>\n\n\n\n The correct answer is:<\/p>\n\n\n\n “The outermost energy level is full.”<\/strong><\/p>\n\n\n\n The atomic number of an element represents the number of protons<\/strong> in its nucleus, and in a neutral atom, it also equals the number of electrons<\/strong>. If an atom has an atomic number of 18<\/strong>, it means the atom has 18 protons and 18 electrons<\/strong>.<\/p>\n\n\n\n Electrons are arranged in energy levels (shells)<\/strong> around the nucleus. The general electron configuration follows the 2-8-8<\/strong> rule:<\/p>\n\n\n\n Thus, the electron configuration for an atom with atomic number 18 is: This means the outermost energy level (third shell) has 8 electrons<\/strong>, which is the maximum number<\/strong> for this shell in a stable atom. Since the outermost shell is full, the atom is chemically stable and does not readily react with other elements<\/strong>.<\/p>\n\n\n\n Thus, the only correct answer is: “The outermost energy level is full.”<\/strong> If the atomic number is 18, then \u00b7 there are seven electrons in the outermost energy level. \u00b7 the atom has eighteen electrons in the nucleus. \u00b7 the outermost energy level is full. \u00b7 All of the above are true. The Correct Answer and Explanation is : The correct answer is: “The outermost energy level […]<\/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-187715","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/187715","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=187715"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/187715\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=187715"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=187715"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=187715"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Explanation:<\/h3>\n\n\n\n
Electron Configuration:<\/strong><\/h4>\n\n\n\n
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2, 8, 8<\/strong><\/p>\n\n\n\nWhy Other Options Are Incorrect:<\/strong><\/h4>\n\n\n\n
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This makes the element Argon (Ar), a noble gas<\/strong>, which is chemically inert because of its full valence shell.<\/p>\n","protected":false},"excerpt":{"rendered":"