Editing Enthalpy change of solution (section)

{{Short description|Change in enthalpy from dissolving a substance}}

In [[thermochemistry]], the '''enthalpy of solution''' ('''heat of solution''' or '''enthalpy of solvation''') is the [[enthalpy]] change associated with the [[Solvation|dissolution]] of a substance in a [[solvent]] at [[Isobaric process|constant pressure]] resulting in infinite dilution.

The enthalpy of solution is most often expressed in [[Joule|kJ]]/[[mole (unit)|mol]] at constant temperature. The energy change can be regarded as being made up of three parts: the [[endothermic]] breaking of [[Chemical bond|bonds]] within the [[solute]] and within the solvent, and the formation of attractions between the solute and the solvent. An [[ideal solution]] has a null [[enthalpy of mixing]]. For a non-ideal solution, it is an [[excess molar quantity]].