Phy essays

Cheat Sheet for Intro/Phy essays Chapter 19  ¡V Chemical Bonding I. Why do atoms form bonds? 1. Most stable atoms have a filled valence shell. Most of the time this is 8 electrons. 2. Lewis Symbols  ¡V electron dot notation showing valence electrons. 3. Atoms form bonds by sharing, gaining, or losing electrons to obtain a filled valence shell. 4. The three major types of chemical bonds are Ionic bonds, Convalent bonds, and Metallic bonds. The type of bond formed depends on the Ionization Energy and electronegativity of the atoms involved. 5. Ionization energy (IE) The energy required to remove a valence electron. Metals have low IE and nonmetals have high IE. 6. Electro of Li and F using Dot Notation  ¡V this e. transfer requires energy. It does take a little energy to remove the e. from the Li, but because both are now stable, the result is a net lowering of energy. B. Size of formed Cations and Anions. 1. Metals tend to get smaller, so they lose e. and thus lose an energy level  ¡V cation. 2. Nonmetals te nd to gain e. so they are larger  ¡V anion. There is no increase in protons, so the nucleus does not pull it in smaller. Instead, it swells to make room. When ionic compounds form, ...