Polar and Nonpolar Bonding Covalent Bonding Susan Baird Dori Delaney Cindy Rothwell Ionic & Molecular Compounds

Polar and Nonpolar Bonding It is a good idea to understand Covalent Bonding, and Electronegativity Before proceeding through this presentation. Ionic & Molecular Compounds

Polar and Nonpolar Bonding From your study into electronegativity you discovered the group 1 (IA) and group 2 (IIA) metals have the lowest electronegativity. Group 16 (VIA) and 17(VIIA) nonmetals have strong electonegativities and attract valance electrons more strongly than any other elements. Ionic & Molecular Compounds

Ionic & Molecular Compounds Nonpolar Bonding When two of the same elements bond they are called diatomic molecules, some examples of this are Hydrogen H2, Oxygen O2 and Nitrogen N2. The atoms in these bonds would have the same electronegativities. This means that both atoms attract the shared electrons to that same extent. This type of bond is known as a Nonpolar Covalent Bond. Ionic & Molecular Compounds

Ionic & Molecular Compounds Polar Covalent Bonds Polar covalent bond are bonds in which electrons are unequally shared between two atoms. Chemists have developed a scheme by which you can use the difference in electronegativities to predict the type of bond that will form between atoms of any two elements. Ionic & Molecular Compounds

Periodic Table with Electronegativity Periodic Table that lists the electronegativities of the elements. Ionic & Molecular Compounds

Polar Covalent Bonds By using a periodic table with the list of electronegativities of each element you can predict what kind of bond will form based on the difference between the electronegativities. Type of Bond Electronegativity Difference Ionic Greater then 1.7 Polar Covalent Between 0.5 and 1.7 Slightly Polar Covalent (refered to as Covalent) Less then 0.5 Nonpolar Covalent Ionic & Molecular Compounds

Polar and Nonpolar Bonding Check out the following video http://ca.youtube.com/watch?v=tSG4R4YZUW8 Ionic & Molecular Compounds

Polar and Nonpolar Bonding Lets look at Fluorine and Potassium. The electronegativity of Fluorine is 3.98 and the electronegativity of Potassium is 0.82 3.98 – 0.82 = 3.16 The difference of 3.16 is much greater then 1.7 therefore this bond must be Ionic. Type of Bond Electronegativity Difference Ionic Greater then 1.7 Polar Covalent Between 0.5 and 1.7 Slightly Polar Covalent Less then 0.5 Nonpolar Covalent Ionic & Molecular Compounds

Polar and Nonpolar Bonding Consider the case of two oxygen atoms. Both atoms have an electronegativity of 3.44 3.44 –3.44 = 0 Therefore this must be a nonpolar covalent Bond. Type of Bond Electronegativity Difference Ionic Greater then 1.7 Polar Covalent Between 0.5 and 1.7 Slightly Polar Covalent Less then 0.5 Nonpolar Covalent Ionic & Molecular Compounds

Polar and Nonpolar Bonding Consider the bond between Carbon and Chlorine in the compound Chloroform (CHCl3) The electronegativity of Carbon is 2.55 and the electronegativity of Chlorine is 3.16. 3.16 – 2.55 = 0.61 The electronegativity difference is between 0.5 and 1.7 therefore this must be a polar covalent bond Type of Bond Electronegativity Difference Ionic Greater then 1.7 Polar Covalent Between 0.5 and 1.7 Slightly Polar Covalent Less then 0.5 Nonpolar Covalent Ionic & Molecular Compounds

Polar and Nonpolar Bonding Check out this video: http://ca.youtube.com/watch?v=3Qz75gb0mrg&feature=related Ionic & Molecular Compounds

Ionic & Molecular Compounds Practice Problem For each of the following pairs of electrons, predict whether a bond between them will be nonpolar covalent, polar covalent or ionic. Carbon and Fluorine Oxygen and Nitrogen Chlorine and Chlorine Copper and Oxygen Silicon and Hydrogen Sodium and Fluorine Iron and Oxygen Manganese and Oxygen Periodic Table Ionic & Molecular Compounds

Ionic & Molecular Compounds Answers Carbon and Fluorine Polar Covalent Oxygen and Nitrogen Slightly Polar Covalent Chlorine and Chlorine Nonpolar Covalent Copper and Oxygen Polar Covalent Silicon and Hydrogen Slightly Polar Covalent Sodium and Fluorine Ionic Iron and Oxygen Polar Covalent Manganese and Oxygen Ionic Ionic & Molecular Compounds

Polar and Nonpolar Bonding Back to Home Page or Back to Polar and Nonpolar Compounds Ionic & Molecular Compounds