2 Ions Ion- Is an atom or group of atoms that has an electric charge When an atom loses an electron it becomes positively charged.When an atom gains an electron it becomes negatively charged.Polyatomic ions are ions that are made of more than one atom, and they have an overall positive or negative charge.
3 Ionic bonds are formed as a result of attraction between positive and negative ions. Ionic compounds consists of positive and negative ions example: Sodium Chloride NaCl
4 Chemical Formulas and Names Ionic compounds are made up of a metal and a nonmetalTo write the formula of an ionic compound you must make sure the compound’s overall charge is zero. (listen to explanation).To name an ionic compound you should name the positive ion first followed by the name of the negative ion. Example: Magnesium Oxide. Notice the ending of negative ion it is always -ide
5 Properties of Ionic Compounds 1. Hard, brittle solids2. Have high melting points3. They make a three dimensional pattern called crystal or crystal lattice.4. Solutions of ionic compounds conduct electric current.