How do you construct a Born-Haber cycle for an ionic compound?

To construct a Born-Haber cycle for an ionic compound, you need to consider the steps involved in the formation of the compound.

A Born-Haber cycle is a thermochemical cycle that relates the various stages involved in the formation of an ionic compound. It is a useful tool in physical chemistry for understanding and calculating lattice energies of ionic compounds. The steps involved in constructing a Born-Haber cycle for an ionic compound are as follows:

1. **Atomisation of the metal:** This is the first step in the cycle. It involves the conversion of a metal from its solid state to gaseous atoms. This is an endothermic process, meaning it requires energy.

2. **Ionisation of the metal atoms:** The gaseous metal atoms are then ionised to form positive ions. This is also an endothermic process as it involves the removal of electrons from the atoms.

3. **Atomisation of the non-metal:** This step involves the conversion of the non-metal from its original state to gaseous atoms. Depending on the state of the non-metal, this could be an endothermic or exothermic process.

4. **Ionisation of the non-metal atoms:** The gaseous non-metal atoms are then ionised to form negative ions. This is an endothermic process.

5. **Formation of the ionic compound:** The positive and negative ions combine to form the ionic compound. This is an exothermic process, meaning it releases energy.

6. **Lattice formation:** The final step is the formation of the lattice structure of the ionic compound. This is also an exothermic process.

The Born-Haber cycle is typically represented as a diagram, with the steps listed above arranged in a circular or looped format. The energy changes associated with each step are indicated on the diagram. The sum of the energy changes for the endothermic processes should equal the energy change for the exothermic process, according to Hess's law. This allows for the calculation of the lattice energy of the ionic compound.