{"id":246719,"date":"2025-07-07T11:09:00","date_gmt":"2025-07-07T11:09:00","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=246719"},"modified":"2025-07-07T11:09:03","modified_gmt":"2025-07-07T11:09:03","slug":"draw-the-lewis-structure-below-calculate-the-number-of-valence-electrons","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/07\/draw-the-lewis-structure-below-calculate-the-number-of-valence-electrons\/","title":{"rendered":"Draw the Lewis Structure below. Calculate the number of valence electrons"},"content":{"rendered":"\n

Molecule #5 SiF6- Draw the Lewis Structure below. Calculate the number of valence electrons. Draw the three-dimensional structure of the molecule using the “wedge and dash” notation. The molecular geometry is: This molecule is polar\/nonpolar (Circle your choice.) Our logic for this choice is: The formal charge on Si is . The hybridization of Si is <\/em><\/strong>. The formal charge on F is . Estimate F-Si-F bond angle. Molecule #6 CClF2. Calculate the number of valence electrons. Draw the Lewis Structure below. Draw the three-dimensional structure of the molecule using the “wedge and dash” notation. The molecular geometry is: This molecule is polar\/nonpolar (Circle your choice). Our logic for this choice is: The formal charge on C is <\/em><\/strong>. The hybridization of C is . The formal charge on ClF is <\/em><\/strong>. Estimate F-C-Cl bond angle.<\/p>\n\n\n\n

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

Molecule #5: SiF6\u00b2\u207b (Hexafluorosilicate Ion)<\/h3>\n\n\n\n
    \n
  1. Valence Electrons Calculation:<\/strong>\n
      \n
    • Silicon (Si) is in group 14, so it has 4 valence electrons.<\/li>\n\n\n\n
    • Fluorine (F) is in group 17, and each fluorine atom has 7 valence electrons. Since there are 6 fluorine atoms, that\u2019s 6 \u00d7 7 = 42 electrons.<\/li>\n\n\n\n
    • The ion has a 2- charge, meaning it has gained 2 additional electrons.<\/li>\n\n\n\n
    • Total valence electrons: 4(from\u00a0Si)+42(from\u00a0F)+2(from\u00a0the\u00a02-\u00a0charge)=484 (\\text{from Si}) + 42 (\\text{from F}) + 2 (\\text{from the 2- charge}) = 484(from\u00a0Si)+42(from\u00a0F)+2(from\u00a0the\u00a02-\u00a0charge)=48 electrons.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
    • Lewis Structure:<\/strong>
      • Silicon (Si) is the central atom, and six fluorine (F) atoms surround it.<\/li>
      • Each fluorine forms a single bond with silicon, using 12 electrons for the bonds.<\/li>
      • The remaining 36 electrons are placed as lone pairs on the fluorine atoms (6 fluorines \u00d7 3 lone pairs = 18 electrons).<\/li>
      • Si has no lone pairs, so the remaining 12 electrons are used in bonding.<\/li><\/ul>The structure will look like: rCopyEdit F | F - Si - F | F<\/code><\/li>\n\n\n\n
      • Three-Dimensional Structure (Wedge and Dash Notation):<\/strong>
        • The molecular geometry is octahedral<\/strong> because six bonds surround the central Si atom.<\/li>
        • The “wedge and dash” notation indicates the 3D arrangement of bonds, with some bonds coming out towards the viewer (wedge) and others going away from the viewer (dash):<\/li><\/ul>rCopyEdit F | F - Si - F \/ \\ F F<\/code><\/li>\n\n\n\n
        • Polarity:<\/strong>\n
            \n
          • This molecule is nonpolar<\/strong> because the fluorine atoms are symmetrically arranged around the silicon atom in an octahedral geometry. The dipoles from each Si-F bond cancel out, resulting in no net dipole moment.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
          • Formal Charge:<\/strong>\n
              \n
            • Formal charge on Si: 0<\/strong> (Si has 4 valence electrons, and it is forming 4 bonds, so no charge).<\/li>\n\n\n\n
            • Formal charge on F: -1<\/strong> (Each fluorine has 7 valence electrons, shares 1 electron with Si, and keeps 3 lone pairs, so the formal charge is -1).<\/li>\n<\/ul>\n<\/li>\n\n\n\n
            • Hybridization:<\/strong>\n
                \n
              • The hybridization of Si is sp\u00b3d\u00b2<\/strong> because it is involved in 6 bonds (an octahedral arrangement).<\/li>\n<\/ul>\n<\/li>\n\n\n\n
              • Bond Angle:<\/strong>\n
                  \n
                • The F-Si-F bond angle is 90\u00b0<\/strong> (in an octahedral geometry, all angles between adjacent bonds are 90\u00b0).<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n
                  \n\n\n\n

                  Molecule #6: CClF2 (Chlorodifluoromethane)<\/h3>\n\n\n\n
                    \n
                  1. Valence Electrons Calculation:<\/strong>\n
                      \n
                    • Carbon (C) is in group 14, so it has 4 valence electrons.<\/li>\n\n\n\n
                    • Chlorine (Cl) is in group 17, and it has 7 valence electrons.<\/li>\n\n\n\n
                    • Fluorine (F) is also in group 17, and each fluorine atom has 7 valence electrons. Since there are 2 fluorine atoms, that\u2019s 2 \u00d7 7 = 14 electrons.<\/li>\n\n\n\n
                    • Total valence electrons: 4(from\u00a0C)+7(from\u00a0Cl)+14(from\u00a0F)=254 (\\text{from C}) + 7 (\\text{from Cl}) + 14 (\\text{from F}) = 254(from\u00a0C)+7(from\u00a0Cl)+14(from\u00a0F)=25 electrons.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
                    • Lewis Structure:<\/strong>
                      • Carbon (C) is the central atom, and it bonds with one chlorine (Cl) and two fluorine (F) atoms.<\/li>
                      • Carbon uses 3 of its electrons to form single bonds with chlorine and fluorine atoms.<\/li>
                      • The remaining electrons are used to complete the octets of chlorine and fluorine atoms.<\/li><\/ul>The structure will look like: rCopyEdit F | F - C - Cl<\/code><\/li>\n\n\n\n
                      • Three-Dimensional Structure (Wedge and Dash Notation):<\/strong>
                        • The molecular geometry is trigonal planar<\/strong> because there are three regions of electron density around the central carbon atom (one single bond to chlorine and two single bonds to fluorine).<\/li>
                        • The “wedge and dash” notation would look like this:<\/li><\/ul>rCopyEdit F | F - C - Cl |<\/code><\/li>\n\n\n\n
                        • Polarity:<\/strong>\n
                            \n
                          • This molecule is polar<\/strong> because the electronegativity difference between C, Cl, and F atoms creates dipole moments. The fluorine atoms are more electronegative than carbon, and chlorine is less electronegative than fluorine. This results in an overall net dipole moment.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
                          • Formal Charge:<\/strong>\n
                              \n
                            • Formal charge on C: 0<\/strong> (C has 4 valence electrons and forms 4 bonds, so no charge).<\/li>\n\n\n\n
                            • Formal charge on Cl: 0<\/strong> (Cl has 7 valence electrons, forms 1 bond, and keeps 3 lone pairs, so no charge).<\/li>\n\n\n\n
                            • Formal charge on F: 0<\/strong> (Each fluorine has 7 valence electrons, forms 1 bond, and keeps 3 lone pairs, so no charge).<\/li>\n<\/ul>\n<\/li>\n\n\n\n
                            • Hybridization:<\/strong>\n
                                \n
                              • The hybridization of C is sp\u00b2<\/strong> because it is involved in three bonds (a trigonal planar geometry).<\/li>\n<\/ul>\n<\/li>\n\n\n\n
                              • Bond Angle:<\/strong>\n
                                  \n
                                • The F-C-Cl bond angle is approximately 120\u00b0<\/strong>, characteristic of a trigonal planar geometry.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n
                                  \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

                                  Molecule #5 SiF6- Draw the Lewis Structure below. Calculate the number of valence electrons. Draw the three-dimensional structure of the molecule using the “wedge and dash” notation. The molecular geometry is: This molecule is polar\/nonpolar (Circle your choice.) Our logic for this choice is: The formal charge on Si is . The hybridization of Si […]<\/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-246719","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/246719","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=246719"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/246719\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=246719"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=246719"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=246719"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}