Giant Covalent Structures (AQA GCSE Chemistry: Combined Science)

Revision Note

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Author

Stewart

Last updated

11 July 2024

Giant covalent structures

Giant covalent structures are solids with high melting points
They have a huge number of non-metal atoms bonded to other non-metal atoms via strong covalent bonds
These structures can also be called giant lattices and have a fixed ratio of atoms in the overall structure
Three examples include diamond, graphite and silicon dioxide

Examiner Tip

If you are unsure whether a covalent structure is a giant structure or consists of small molecules, think about whether it is a solid, liquid or gas at room temperature. Giant covalent structures are solids at room temperature, those consisting of small molecules are liquids and gases.

Properties of giant covalent structures

Diamond, graphite and silicon dioxide all have giant covalent structures
- Diamond and graphite are made from carbon atoms
- Silicon dioxide (silica) is made from silicon and oxygen atoms
All giant covalent structures have high melting points because:
- There are strong covalent bonds between atoms
- These require lots of energy to overcome