{"id":245595,"date":"2025-07-06T09:38:58","date_gmt":"2025-07-06T09:38:58","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=245595"},"modified":"2025-07-06T09:39:00","modified_gmt":"2025-07-06T09:39:00","slug":"fix-any-errors-in-these-proposed-electron-configurations","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/06\/fix-any-errors-in-these-proposed-electron-configurations\/","title":{"rendered":"Fix any errors in these proposed electron configurations"},"content":{"rendered":"\n

Fix any errors in these proposed electron configurations_ number of electrons in atom proposed electron configuration 20 Is” 2s 2p 3s’ Jp” 34? 30 Is Ip 2s” 2p” 2d 3s” 3p 14 Is” 2s” 2p” 2d 3s<\/p>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n

1. Atomic number 20 (Calcium, Ca):<\/h3>\n\n\n\n

Proposed electron configuration:
1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074<\/strong><\/p>\n\n\n\n

This configuration is incorrect because the 3p orbital can hold a maximum of 6 electrons. Calcium (with 20 electrons) should have a configuration that fills the orbitals up to 4s\u00b2.<\/p>\n\n\n\n

Correct electron configuration:<\/strong>
1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2076 4s\u00b2<\/strong><\/p>\n\n\n\n

2. Atomic number 34 (Selenium, Se):<\/h3>\n\n\n\n

Proposed electron configuration:
1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074 3d\u00b9\u2070<\/strong><\/p>\n\n\n\n

This is close but slightly incorrect. The 3d orbital fills after the 4s orbital according to the Aufbau principle. For selenium (34 electrons), the correct configuration should have filled the 4s orbital before the 3d orbital.<\/p>\n\n\n\n

Correct electron configuration:<\/strong>
1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2076 4s\u00b2 3d\u00b9\u2070 4p\u2074<\/strong><\/p>\n\n\n\n

3. Atomic number 14 (Silicon, Si):<\/h3>\n\n\n\n

Proposed electron configuration:
1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2<\/strong><\/p>\n\n\n\n

This configuration is incomplete because silicon (atomic number 14) has 14 electrons, but the proposed configuration only accounts for 12.<\/p>\n\n\n\n

Correct electron configuration:<\/strong>
1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u00b2<\/strong><\/p>\n\n\n\n

Explanation:<\/h3>\n\n\n\n
    \n
  • The Aufbau principle<\/strong> states that electrons fill orbitals starting from the lowest energy level (1s) and proceed to higher levels (2s, 2p, 3s, 3p, 4s, 3d, etc.) in a systematic order.<\/li>\n\n\n\n
  • The Pauli exclusion principle<\/strong> ensures that no two electrons in the same atom have the same set of quantum numbers, which is why orbitals fill with two electrons (one with spin-up and the other with spin-down).<\/li>\n\n\n\n
  • Hund’s rule<\/strong> states that electrons fill degenerate orbitals (orbitals with the same energy level, like 3p or 5p) singly before pairing up to minimize repulsion.<\/li>\n<\/ul>\n\n\n\n

    So, the corrected electron configurations are based on filling the orbitals correctly according to these rules.<\/p>\n\n\n\n

    \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

    Fix any errors in these proposed electron configurations_ number of electrons in atom proposed electron configuration 20 Is” 2s 2p 3s’ Jp” 34? 30 Is Ip 2s” 2p” 2d 3s” 3p 14 Is” 2s” 2p” 2d 3s The Correct Answer and Explanation is: 1. Atomic number 20 (Calcium, Ca): Proposed electron configuration:1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 […]<\/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-245595","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/245595","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=245595"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/245595\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=245595"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=245595"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=245595"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}