A Level Chemistry OCR Practice Exam

What characterizes a giant covalent lattice?

1. A disordered arrangement of atoms

2. A strong network of atoms held by ionic bonds

3. A three-dimensional structure bonded by strong covalent bonds

4. A structure made up of molecules with weak interactions

The correct answer is: A three-dimensional structure bonded by strong covalent bonds

A giant covalent lattice is characterized by a three-dimensional structure where an extensive network of atoms is interconnected by strong covalent bonds. This type of bonding leads to a solid with very high melting and boiling points, significant hardness, and electrical insulation in most cases. The covalent bonds in such structures are directional and form a stable and rigid framework, differentiating them from other types of materials. In contrast, the other options describe characteristics that do not align with the properties of a giant covalent lattice. For instance, a disordered arrangement of atoms would suggest a non-crystalline structure, which is not typical of giant covalent lattices known for their crystalline nature. Ionic bonds, while they create strong structures, are not the primary bonding type in a giant covalent lattice, which relies solely on covalent bonding. Lastly, mentioning weak interactions implies a molecular structure found in covalent compounds rather than the strong, extensive bonding found in giant covalent lattices. Therefore, the defining feature of a giant covalent lattice is indeed its three-dimensional arrangement bonded by strong covalent interactions.