Construct Born-Haber cycles for ionic compounds.

In the subtopic Born-Haber cycles (A-level only), this AQA A-Level Chemistry 7405 learning objective focuses on construct Born-Haber cycles for ionic compounds. It belongs to Thermodynamics (A-level only), so revision should stay anchored to this exact subtopic rather than drifting into a generic GCSE-level chemistry summary. Approved keywords to use include Born-Haber cycle. Lattice enthalpy. means the enthalpy change that occurs when gaseous ions combine to form one mole of an ionic solid; it is a measure of the strength of the ionic lattice and is calculated from the Born–Haber cycle Avoid the mistake of students often forget to include all relevant enthalpy changes, such as sublimation and ionization energies, when constructing Born-Haber cycles; instead, to correctly construct a Born-Haber cycle, include all necessary enthalpy changes: the enthalpy of formation, sublimation, ionization, and electron affinity. For example, use the formula: ΔH_f = ΔH_sublimation + ΔH_ionization + ΔH_electron_affinity + ΔH_lattice. Substitute the values for each enthalpy change, perform the calculations, and ensure all steps are represented in the cycle For exam answers, when constructing a Born-Haber cycle, start by identifying the enthalpy changes involved in the formation of the ionic compound from its elements. Use Hess's law to relate these changes