Bulk Properties
- Different compounds have different structures and bond types/strengths that give rise to bulk properties
- Examples of bulk properties include electrical conductivity, and melting/boiling points
- Individual atoms do not possess these physical properties, rather they arise due to many atoms, ions or molecules acting together
- An explanation of some bulk properties are listed below:
Summary Table of Some Bulk Properties
Brittle v Malleable
- Ionic and giant covalent substances are also brittle whereas metals are malleable
- A brittle substance cracks or breaks when an external force is applied
- Malleable substances change shape without cracking or breaking
- Metals are malleable as their atoms are arranged in layers which slide over each other when force is applied
- Giant Covalent and Ionic structures have their bonds broken if force is applied and as a result break
Diagram explaining the malleability of a metal
Polymers
- Most are solid at room temperature
- There are strong covalent bonds between atoms but intermolecular forces between polymer molecules
- The intermolecular forces are larger than those between simple covalent molecules and therefore need more energy to break but weaker than ionic or covalent bonds.
Examiner Tip
Remember, ionic and metallic compounds all have giant structures as well, not just covalent.