Enthalpy Change of Solution

When an ionic salt is dissolved in water, a temperature change is observed. This i measured by the standard enthalpy change of solution, which changes for different salts, depending on the properties of the ions and the strength of the ionic bonds.

When a salt dissolves in water, two things happen:

• Breakdown of the ionic lattice into gaseous ions
• hydration of the gaseous ions by water

The resulting energy change depends on the balance between the enrgy changes of these seperate processes

Breakdown of lattice

Energy is needed to break the lattice structure of the ionic compund, as the electrostatic force between the ions…