{"id":234041,"date":"2025-06-13T17:12:07","date_gmt":"2025-06-13T17:12:07","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=234041"},"modified":"2025-06-13T17:12:09","modified_gmt":"2025-06-13T17:12:09","slug":"how-does-the-size-of-atoms-atomic-size-generally-vary-in-going-from-left-to-right-in-a-period-of-the-periodic-table","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/13\/how-does-the-size-of-atoms-atomic-size-generally-vary-in-going-from-left-to-right-in-a-period-of-the-periodic-table\/","title":{"rendered":"How does the size of atoms (atomic size) generally vary in going from left to right in a period of the periodic table"},"content":{"rendered":"\n<p>How does the size of atoms (atomic size) generally vary in going from left to right in a period of the periodic table? Why does it vary this way<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p><strong>Correct Answer:<\/strong><br>As we move from left to right across a period in the periodic table, <strong>atomic size (atomic radius) generally decreases<\/strong>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p><strong>Detailed Explanation (Textbook Style):<\/strong><br>The atomic size, also known as atomic radius, refers to the distance from the nucleus of an atom to the outermost electrons. This size is influenced by two key factors: the number of protons in the nucleus (nuclear charge) and the number of energy levels (electron shells).<\/p>\n\n\n\n<p>When moving <strong>from left to right across a period<\/strong> in the periodic table, each successive element has <strong>one more proton and one more electron<\/strong> than the previous one. However, all these electrons are added to the <strong>same principal energy level<\/strong> (same shell). This means that the <strong>electron shielding remains relatively constant<\/strong> because no new inner shells are added.<\/p>\n\n\n\n<p>At the same time, the <strong>nuclear charge increases<\/strong> due to the addition of more protons in the nucleus. A higher nuclear charge means a stronger positive pull on the negatively charged electrons. Since the added electrons are not increasing the shielding effect significantly (they are in the same shell), the <strong>increased nuclear attraction pulls the electron cloud closer to the nucleus<\/strong>, effectively reducing the atomic radius.<\/p>\n\n\n\n<p>Therefore, <strong>the atomic size decreases<\/strong> from left to right across a period because the electrons are pulled in closer to the nucleus due to the increasing nuclear charge, without a corresponding increase in shielding.<\/p>\n\n\n\n<p>For example, consider the elements in Period 2:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Lithium (Li)<\/strong> has a larger atomic radius than<\/li>\n\n\n\n<li><strong>Beryllium (Be)<\/strong>, which is larger than<\/li>\n\n\n\n<li><strong>Boron (B)<\/strong>, and so on, up to<\/li>\n\n\n\n<li><strong>Fluorine (F)<\/strong> and <strong>Neon (Ne)<\/strong>, which have much smaller atomic radii.<\/li>\n<\/ul>\n\n\n\n<p>This trend continues consistently across all periods in the periodic table.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/06\/learnexams-banner5-452.jpeg\" alt=\"\" class=\"wp-image-234042\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>How does the size of atoms (atomic size) generally vary in going from left to right in a period of the periodic table? Why does it vary this way The Correct Answer and Explanation is: Correct Answer:As we move from left to right across a period in the periodic table, atomic size (atomic radius) generally [&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-234041","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/234041","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=234041"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/234041\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=234041"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=234041"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=234041"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}