1. 7.2 Objectives
Describe the formation of ionic bonds and the structure of ionic compounds.
Generalize about the strength of ionic bonds based on the physical properties of ionic compounds.
Categorize ionic bond formation as exothermic or endothermic.

2. Oppositely charged ions attract each other, forming electrically neutral ionic compounds.

3. Formation of an Ionic Bond
Ionic bond - electrostatic force that holds oppositely charged particles together.
Compounds that contain ionic bonds are called ionic compounds.

4. Formation of an Ionic Bond (cont.)

5. Properties of Ionic Compounds
Ionic compounds formed of ionic crystals.
Repeating pattern of particle packing in an ionic compound.

6. Properties of Ionic Compounds (cont.)
Crystal lattice - three-dimensional geometric arrangement of particles
Responsible for the structure of many minerals.

7. Properties of Ionic Compounds (cont.)
Melting point, boiling point, and hardness depend on the strength of the attraction.

8. Properties of Ionic Compounds (cont.)
Two factors needed to conduct electricity:
Charged particles
Electrons need to be able to move freely
Solid ions poor conductor of electricity
Ions locked into position - electrons cannot flow freely.
Liquid ions conduct electricity easily
Ions free to move.

9. Properties of Ionic Compounds (cont.)

10. Energy and the Ionic Bond
The energy required to separate 1 mole of ions in an ionic compound is referred to as the lattice energy.
The smaller the ion, the greater the attraction.

11. Energy and the Ionic Bond (cont.)

12. Assessment
Why are solid ionic compounds poor conductors of electricity?
A. They are non-metals.
B. They are electrolytes.
C. They have electrons that cannot flow freely.
D. Solids do not conduct electricity.

13. Assessment
Why are solid ionic compounds poor conductors of electricity?
C. They have electrons that cannot flow freely.

14. Assessment What is the electrostatic charge holding two ions together?
A. covalent bond
B. pseudo-noble gas bond
C. crystal lattice bond
D. ionic bond

15. Assessment What is the electrostatic charge holding two ions together?
D. ionic bond