{"id":240570,"date":"2025-07-03T10:22:26","date_gmt":"2025-07-03T10:22:26","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=240570"},"modified":"2025-07-03T10:22:28","modified_gmt":"2025-07-03T10:22:28","slug":"draw-the-molecular-orbital-mo-electron-diagram-for-the-b2-molecular-ion","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/03\/draw-the-molecular-orbital-mo-electron-diagram-for-the-b2-molecular-ion\/","title":{"rendered":"Draw the molecular orbital (MO) electron diagram for the B2 molecular ion"},"content":{"rendered":"\n

Draw the molecular orbital (MO) electron diagram for the B2 molecular ion. Be sure vour diagram contains all of the electrons in the ion, including ay core electrons_ Energy<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

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

Here is the completed molecular orbital (MO) diagram for the B\u2082\u00b2\u207a molecular ion.<\/p>\n\n\n\n

Explanation of the MO Diagram<\/h3>\n\n\n\n

To construct the molecular orbital (MO) diagram for the B\u2082\u00b2\u207a ion, we first determine the total number of electrons. A neutral boron atom (B) has an atomic number of 5, meaning it has 5 electrons. A neutral diatomic boron molecule (B\u2082) would therefore have 10 electrons. The B\u2082\u00b2\u207a ion has a +2 charge, indicating it has lost two electrons, leaving a total of 8 electrons to place in the MO diagram.<\/p>\n\n\n\n

The diagram is built from the atomic orbitals (AOs) of the two boron atoms, which are the 1s, 2s, and 2p orbitals. These are shown on the left and right sides. When these AOs combine, they form an equal number of molecular orbitals (MOs), shown in the center, arranged by increasing energy. For elements in the second period up to and including nitrogen, significant s-p mixing occurs, which causes the \u03c0\u2082p orbitals to be lower in energy than the \u03c3\u2082p orbital. The energy order for B\u2082 is therefore:
\u03c3\u2081s < \u03c3\u2081s < \u03c3\u2082s < \u03c3<\/em>\u2082s < \u03c0\u2082p < \u03c3\u2082p < \u03c0\u2082p < \u03c3<\/em>\u2082p<\/p>\n\n\n\n

The 8 electrons of the B\u2082\u00b2\u207a ion are then filled into these molecular orbitals according to the Aufbau principle (lowest energy first), the Pauli exclusion principle (two electrons per orbital with opposite spins), and Hund’s rule.<\/p>\n\n\n\n

    \n
  1. Two electrons fill the \u03c3\u2081s bonding orbital.<\/li>\n\n\n\n
  2. Two electrons fill the \u03c3*\u2081s antibonding orbital.<\/li>\n\n\n\n
  3. Two electrons fill the \u03c3\u2082s bonding orbital.<\/li>\n\n\n\n
  4. The final two electrons fill the \u03c3*\u2082s antibonding orbital.<\/li>\n<\/ol>\n\n\n\n

    The resulting electron configuration for B\u2082\u00b2\u207a is (\u03c3\u2081s)\u00b2(\u03c3\u2081s)\u00b2(\u03c3\u2082s)\u00b2(\u03c3<\/em>\u2082s)\u00b2.<\/p>\n\n\n\n

    From this diagram, we can calculate the bond order, which is a measure of the number of chemical bonds between the two atoms. The formula is:
    Bond Order = \u00bd (Number of bonding electrons – Number of antibonding electrons)
    Bond Order = \u00bd (4 – 4) = 0<\/p>\n\n\n\n

    A bond order of zero indicates that there is no net chemical bond between the two boron ions. Therefore, the B\u2082\u00b2\u207a ion is predicted to be unstable and unlikely to exist. Since all electrons in the MO diagram are paired, the ion is diamagnetic.<\/p>\n\n\n\n

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

    Draw the molecular orbital (MO) electron diagram for the B2 molecular ion. Be sure vour diagram contains all of the electrons in the ion, including ay core electrons_ Energy The Correct Answer and Explanation is: Here is the completed molecular orbital (MO) diagram for the B\u2082\u00b2\u207a molecular ion. Explanation of the MO Diagram To construct […]<\/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-240570","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/240570","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=240570"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/240570\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=240570"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=240570"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=240570"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}