International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

What describes the arrangement of ions in an ionic solid?

1. Covalent networks

2. Metallic lattices

3. Giant ionic lattice

4. Simple molecular structure

The correct answer is: Giant ionic lattice

The arrangement of ions in an ionic solid is best described as a giant ionic lattice. In this structure, positively and negatively charged ions are held together by strong electrostatic forces of attraction, forming a three-dimensional network throughout the material. This lattice structure is characteristic of ionic compounds, leading to properties such as high melting and boiling points, as well as the ability to conduct electricity when melted or dissolved in water due to the mobility of the ions. Other structures mentioned, such as covalent networks and metallic lattices, refer to different bonding types. Covalent networks involve a vast network of atoms held together by covalent bonds, while metallic lattices refer to the arrangement of metal atoms in a metallic bond context where electrons are delocalized. A simple molecular structure typically involves discrete molecules held together by weaker intermolecular forces, such as van der Waals forces or hydrogen bonds, rather than the strong ionic interactions found in a giant ionic lattice.