1. Ionic Solids
201 Chemistry

2. Types of solids Solids are classified according to their properties
Properties of solids depend on:
Particle type
Bonding within and between the particles

3. Kaupapa / Learning Outcome
At the end of this lesson I will be able to explain the properties of ionic solids in terms of their structure and bonding.

4. Ionic Solids Eg. Sodium Chloride High melting point
Conducts electricity when molten
Hard but brittle

5. Ionic Solids
Ionic solids are made of ions which sit in a 3D network of positive and negative ions. The ions are held together by electrostatic attractions (ionic bonds)

6. Melting Point of Ionic Solids
Ionic solids have high melting and boiling points
Because the ions are held together by very strong electrostatic forces (ionic bonds)
Which means lots of energy is required to break the bonds

7. Conductivity of Ionic Solids
Ionic solids do not conduct when in solid form
the ions are in fixed positions and cannot move
But when molten or aqueous the ions are free to move and so can conduct electricity.

8. Hardness of Ionic Solids
Hard due to the strong electrostatic attractions between the ions

9. Brittleness of Ionic Solids
Ionic solids are very brittle
The ions are in fixed positions
If a force is applied – the ions are moved out of position, like charges line up and the repulsive forces push the ions apart and the crystal breaks.

11. Solubility
Ionic solids are soluble in polar solvents eg. Water Attractions between the water molecules and the ions are strong enough to over come the attractions between the ions.