Chemical bond

Chemistry 1210: Introduction to General Chemistry Dr. Gina M. Florio 15 Nov. 2012 Jespersen, Brady, Hyslop Chapter 9 Chemical Bonding: General Concepts Ionic Bonds Ch. 9.2 Ionic bonds are the attraction between positive and negative ions in an ionic compound. e.g. NaCl An electron is transferred from the metal (Na) to the nonmetal (Cl): Ionic compounds form when metals and nonmetals react and they are held together by ionic bonds. Compounds (ionic and molecular) are formed due to a decrease (lowering) of the potential energy of system. Net energy change associated with the electron transfer reaction. So, why does NaCl (s) form at all? 2 Lattice Energy of Ionic Compounds Ch. 9.2 The energy needed to produce separated gaseous ions from one mole of the solid is the lattice energy:

Chemistry 1220: Introduction to General Chemistry Dr. Gina M. Florio 08 Dec. 2012 Jespersen, Brady, Hyslop Chapter 12.1-12.5 Intermolecular Attractions and the Properties of Liquids and Solids 1 Phases of Matter Intermolecular Interactions (interactions between molecules) determine the physical properties/states of matter . Important differences between gases, solids, and liquids: Gases Expand to fill their container Liquids Retain volume, but not shape Solids Retain volume and shape Types of Intermolecular Interactions Dipole-Dipole (including Hydrogen Bonding) Ion-Dipole Dispersion (Induced Dipole-Induced Dipole) Ion-Induced Dipole Intermolecular Interactions (interactions between molecules):