{"id":254470,"date":"2025-07-12T14:12:22","date_gmt":"2025-07-12T14:12:22","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=254470"},"modified":"2025-07-12T14:12:25","modified_gmt":"2025-07-12T14:12:25","slug":"draw-the-lewis-structures-of-krf4-sef5","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/12\/draw-the-lewis-structures-of-krf4-sef5\/","title":{"rendered":"Draw the Lewis structures of: KrF4, SeF5-"},"content":{"rendered":"\n
. Draw the Lewis structures of: KrF4, SeF5-. b. What is the geometric structure around the central atom in each of the ions in section a? c. What is the hybridization of the central atom in each of the ions in section a? d. What are the angles of the F-Kr-F, F-Se-F relationships in each of the ions in section a? e. What is the oxidation number of the central atom in each of the ions in section a?<\/p>\n\n\n\n
The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n
Let’s go through each part of the question:<\/p>\n\n\n\n
Krypton (Kr) has 8 valence electrons (Group 18 element).<\/li>\n\n\n\n
Fluorine (F) has 7 valence electrons, and there are 4 F atoms.<\/li>\n\n\n\n
Arrange the F atoms around the Kr atom. Each F atom forms a single bond with Kr.<\/li>\n\n\n\n
After bonding, each F atom will have 3 lone pairs of electrons to satisfy the octet rule. The Kr atom will have 2 lone pairs.<\/li>\n<\/ol>\n\n\n\n
So, the Lewis structure<\/strong> of KrF4 shows:<\/p>\n\n\n\n
\n
Kr at the center with 4 F atoms surrounding it, each with a single bond.<\/li>\n\n\n\n
Kr has 2 lone pairs of electrons.<\/li>\n<\/ul>\n\n\n\n
SeF5- (Selenate Ion)<\/strong><\/h4>\n\n\n\n\n
Selenium (Se) is in Group 16, so it has 6 valence electrons.<\/li>\n\n\n\n
Fluorine (F) has 7 valence electrons, and there are 5 F atoms.<\/li>\n\n\n\n
After forming single bonds with each F atom, the Se atom has a formal charge of -1 because the ion carries an extra electron.<\/li>\n\n\n\n
Se will have 1 lone pair of electrons.<\/li>\n<\/ol>\n\n\n\n
The Lewis structure<\/strong> of SeF5-:<\/p>\n\n\n\n
\n
Se at the center with 5 F atoms around it.<\/li>\n\n\n\n
Se has 1 lone pair of electrons, and there is a -1 charge on the ion.<\/li>\n<\/ul>\n\n\n\n\n\n\n\n
b. Geometric Structure<\/h3>\n\n\n\n
KrF4<\/strong><\/h4>\n\n\n\n
\n
The geometry<\/strong> around the central Kr atom is square planar<\/strong>. This occurs because the 4 bonds to the F atoms are arranged in a plane, with the 2 lone pairs on Kr occupying opposite sides of the square.<\/li>\n<\/ul>\n\n\n\n
SeF5-<\/strong><\/h4>\n\n\n\n
\n
The geometry<\/strong> around the central Se atom is trigonal bipyramidal<\/strong>. The 5 F atoms are arranged in 5 positions around Se, with 3 F atoms in the equatorial plane and 2 in the axial positions.<\/li>\n<\/ul>\n\n\n\n\n\n\n\n
c. Hybridization<\/h3>\n\n\n\n
KrF4<\/strong><\/h4>\n\n\n\n
\n
The hybridization<\/strong> of the central Kr atom is sp3d2<\/strong>. The Kr atom has 4 bonding regions and 2 lone pairs, resulting in 6 regions of electron density around the Kr atom, requiring sp3d2 hybridization.<\/li>\n<\/ul>\n\n\n\n
SeF5-<\/strong><\/h4>\n\n\n\n
\n
The hybridization<\/strong> of the central Se atom is also sp3d2<\/strong>. The Se atom has 5 bonding regions and 1 lone pair, which means it has 6 regions of electron density, requiring sp3d2 hybridization.<\/li>\n<\/ul>\n\n\n\n\n\n\n\n
d. Bond Angles (F-Kr-F, F-Se-F)<\/h3>\n\n\n\n
KrF4<\/strong><\/h4>\n\n\n\n
\n
The bond angle between F-Kr-F is 90\u00b0<\/strong> due to the square planar geometry. The F atoms are in the same plane, and the lone pairs on Kr push the F atoms into a 90\u00b0 arrangement.<\/li>\n<\/ul>\n\n\n\n
SeF5-<\/strong><\/h4>\n\n\n\n
\n
The bond angle between F-Se-F is 90\u00b0<\/strong> for the axial positions and 120\u00b0<\/strong> for the equatorial positions. This is typical of trigonal bipyramidal geometry, with the axial F atoms at 90\u00b0 to the equatorial ones and the equatorial F atoms at 120\u00b0 to each other.<\/li>\n<\/ul>\n\n\n\n\n\n\n\n
e. Oxidation Number<\/h3>\n\n\n\n
KrF4<\/strong><\/h4>\n\n\n\n
\n
The oxidation number of Kr in KrF4 is +4<\/strong>. Fluorine is always -1, and with 4 F atoms, the sum of the oxidation states must be 0. Therefore, Kr must be +4 to balance the 4(-1) from F.<\/li>\n<\/ul>\n\n\n\n
SeF5-<\/strong><\/h4>\n\n\n\n
\n
The oxidation number of Se in SeF5- is +5<\/strong>. Fluorine is -1, and with 5 F atoms, the total negative charge is -5. Since the ion carries a -1 charge, Se must be +5 to balance the total charge (-5 + 5 = -1).<\/li>\n<\/ul>\n\n\n\n\n\n\n\n
Final Summary:<\/h3>\n\n\n\n
\n
KrF4<\/strong>: Square planar geometry, sp3d2 hybridization, bond angle of 90\u00b0, oxidation number of Kr is +4.<\/li>\n\n\n\n
SeF5-<\/strong>: Trigonal bipyramidal geometry, sp3d2 hybridization, bond angles of 90\u00b0 and 120\u00b0, oxidation number of Se is +5.<\/li>\n<\/ul>\n\n\n\n<\/figure>\n","protected":false},"excerpt":{"rendered":"
. Draw the Lewis structures of: KrF4, SeF5-. b. What is the geometric structure around the central atom in each of the ions in section a? c. What is the hybridization of the central atom in each of the ions in section a? d. What are the angles of the F-Kr-F, F-Se-F relationships in each […]<\/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-254470","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/254470","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=254470"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/254470\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=254470"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=254470"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=254470"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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