1. Ionic Compounds LG: I can write formulas and draw Lewis structures for ionic compounds

2. Chemical Compounds A compound is a group of two or more atoms/ions held together by chemical bonds – Compounds can be ionic or molecular A chemical bond is the force holding two atoms or ions together in a compound (“invisible glue”) – Chemical bonds can be ionic or covalent

3. Formation of Ionic Compounds An ionic compound forms when a nonmetal removes an electron from a metal. – The resulting ions have opposite charge and are attracted to each other – This electrostatic attraction is an ionic bond

4. Structure of Ionic Compounds Ionic compounds do not exist in the simplest ratio of ions; they form large arrangements called crystal lattice structures Crystals of different ionic compounds have different 3-D shapes The smallest repeating unit is called a formula unit

5. Properties of Ionic Compounds Hard & have high melting and boiling points – Each +ve ion is attracted to many –ve ions (& vice versa); bonds resist being stretched Brittle – A sudden force offsets the lattice structure and causes ions with the same charge to come into contact and repel Ionic compound are soluble in water and form electrolytes – Ions separate from one another and can carry electric charge

6. Using Lewis Structures to Represent Ionic Bonds Lewis Dot Diagrams for atoms: – ie. Lewis Dot diagrams for ions: – ie. Lewis structures for ionic compounds: – Ie. The lowest ratio of ions that produces a neutral compound is the chemical formula: NaCl

7. Practice: Lewis Structures Draw Lewis diagrams for the following atoms: MgLiFONKCaS Draw Lewis for each element above as an ion: Draw Lewis structures for the following ionic compounds: Lithium FluorideMagnesium Fluoride Potassium OxideCalcium Sulfide Lithium NitrideMagnesium Nitride Write chemical formulas for each compounds above:

8. Homework New Book: Pg. 60 # 1 – 5, 7, 8 Old Book: Pg. 71 # 1 – 5, Pg. 73 # 9, Pg. 74 # 11