6.1: Ions Ions can be positively charged or negatively charged. A Lewis diagram is used to show how electrons are transferred to make ions and ionic compounds. 6.2: Formulas for Ionic Compounds Proper chemical formulas for ionic compounds balance the total positive charge with the total negative charge. Groups of atoms with an overall charge, called polyatomic ions, also exist. 6.3: Ionic Nomenclature Each ionic compound has its own unique name that comes from the names of the ions. After learning a few more details about the names of individual ions, you will be a step away from knowing how to name ionic compounds. This section begins the formal study of nomenclature, the systematic naming of chemical compounds. 6.3.1: Practice Naming 6.4: Covalent Compounds - Formulas and Names The chemical formula of a simple covalent compound can be determined from its name. The name of a simple covalent compound can be determined from its chemical formula. 6.5: Acids An acid is a compound of the H+ ion dissolved in water. Acids have their own naming system. Acids have certain chemical properties that distinguish them from other compounds. 6.5.1: More Practice Naming 6.6: Lewis Structures of Ionic Compounds- Electrons Transferred The tendency to form species that have eight electrons in the valence shell is called the octet rule. The attraction of oppositely charged ions caused by electron transfer is called an ionic bond. The strength of ionic bonding depends on the magnitude of the charges and the sizes of the ions. 6.6.1: Covalent Lewis Structures- Electrons Shared 6.6.2: Writing Lewis Structures for Covalent Compounds 6.6.3: Practice Lewis Structures 6.7: Predicting the Shapes of Molecules The approximate shape of a molecule can be predicted from the number of electron groups and the number of surrounding atoms. 6.7.1: Practice Shape 6.8: Electronegativity and Polarity - Why Oil and Water Don’t Mix Covalent bonds can be nonpolar or polar, depending on the electronegativities of the atoms involved. Covalent bonds can be broken if energy is added to a molecule. The formation of covalent bonds is accompanied by energy given off. Covalent bond energies can be used to estimate the enthalpy changes of chemical reactions. 6.8.1: Practice Polarity