A Level Chemistry OCR Practice Exam

What characterizes a giant metallic lattice?

1. A three-dimensional structure of positive ions and delocalised electrons, bonded together by strong metallic bonds.

2. A network of covalent bonds between neutral atoms.

3. A structure made entirely of ions in solution.

4. A random structure with little interaction between entities.

The correct answer is: A three-dimensional structure of positive ions and delocalised electrons, bonded together by strong metallic bonds.

A giant metallic lattice is characterized by a three-dimensional structure composed of positive ions surrounded by a sea of delocalized electrons. This arrangement is what gives rise to strong metallic bonds, which hold the ions in place and contribute to the unique properties of metals, such as electrical conductivity and malleability. The delocalization of electrons allows them to move freely throughout the lattice, facilitating the flow of electric current and enabling the lattice to maintain its structure under stress. In contrast, the other options describe different types of bonding or structures that do not accurately represent a giant metallic lattice. A network of covalent bonds pertains to covalent solids, which are distinct from metallic structures due to the localized nature of their electrons. A structure made entirely of ions in solution would not qualify as a lattice; instead, it refers to ions dispersed in a solvent. Lastly, a random structure with little interaction does not capture the organized and interactive nature of the ions and electrons in a giant metallic lattice.