Catalyst Draw the ionic compound that results from combining Magnesium and Chlorine. Draw the ionic compound that results from combining Calcium and Permanganate (MnO 4 - ) End Million Dollar Ionic Pyramid + Organic Chemist Average Salary: $70,000 LECTURE 2.3 COVALENT BONDS AND LEWIS STRUCTURES Todays Learning Targets LT 2.6 I can identify a compound containing a covalent bond and discuss how electrons aid in the formation of covalent bonds. LT 2.7 For a given covalent compound, I can draw a Lewis Dot diagram for the compound and explain how it illustrates the covalent bond. W HAT ARE COVALENT BONDS ? Chemical Bonding Ionic Bonds Metallic Bonds Covalent Bonds I. Covalent Bonding This is a bond between only non-metals. In a covalent bond, the electrons are shared between the elements so that each can get an Octet. Most molecules in biology are covalent compounds COVALENT BONDS PLAY WELL TOGETHER How do you show electrons being shared? Covalent Bonds Share! II. Electronegativity and Covalent Bonding Because electrons are not completely transferred, covalent bonds form between molecules that have similar electronegativities This is why metals cannot form covalent bonds. Lewis Structures for Ionic Bonds Na Cl Lewis Structures for Ionic Bonds [Na] + [Cl] - Chemical Bonding Ionic Bonds Metallic Bonds Covalent Bonds II. Drawing Lewis Structures Halogens and hydrogen form only one bond and are located at the end of a molecule. The central atom is always carbon (if it is present) and/or the element that has the lowest electronegativity. Class Example Draw the Lewis structure for H 2 S My Turn! Draw the structure for NH 3 Stop and Jot Draw the Lewis structure for C 2 H 6 III. Single, Double and Triple Bonds Elements can share more then one set of electrons. They can also form double and triple bonds. Single bond = 2 electrons Double bond = 4 electrons Triple bond = 6 electrons Class Example Draw the Lewis Structure for CH 2 O My Turn! With your table, draw the structure of C 2 H 2 Stop and Jot Draw the structure of HCN SUMMARIZE Collaborative -Investigate and Check At your table number off 1 through 4 Odd numbers (1 & 3) will solve problems in the left column. Even numbers (2 & 4) will solve problems in the right column After a pair solves a problem they will pass the problems to another pair to check that they did the problem correctly. Work through the problems in order. Exit Ticket 1.Draw the Lewis structure for H 2 O 2.Draw the Lewis structure for NH 3 3.Draw the Lewis structure for HCN Rate Yourself! Using your exit ticket score, rate yourself 1 4 on LT 2.7 Closing Time Homework 2.4 Lewis Structure Practice TEST NEXT THURSDAY/FRIDAY