Classification of Solids & Properties of Ionic Solids br Classification of Solids br 1. Ionic Solids br 2. Covalent Solids br 3. Metalic Solids br 4. Molecular Solids br Properties of Ionic Solids: br 1. Physical State br 2. Melting and Boiling Points br 3. Non-directional and close packing br 4. Radius Ratio br 5. Formula Mass br 6. Electrical conductivity br 7. Brittleness br 8. Density br 9.