Which term describes the energy change when a mole of ions is hydrated?

The term that describes the energy change when a mole of ions is hydrated is known as enthalpy change of hydration. This process involves the interaction between water molecules and ions when they dissolve in water. During hydration, water molecules surround the ions, stabilizing them in solution. The energy released when water molecules form interactions with the ions is an exothermic process, resulting in a negative value for the enthalpy change of hydration.

This concept is essential in understanding solubility and the energetics involved in dissolving ionic compounds in water. The stronger the interaction between the ions and water molecules, the greater the enthalpy change of hydration, indicating a more favorable dissolution process. In contrast, the standard enthalpy change of vaporization relates to the energy required to convert a liquid into a vapor, the standard enthalpy change of solution involves the overall energy change when a solute dissolves, and bond energy refers to the energy required to break bonds in a molecule, which are different concepts.