Solvatationsenthalpien

Solvatationsenthalpien, also known as solvation enthalpy, refers to the enthalpy change that occurs when one mole of a solute dissolves in a solvent. This process involves the interaction between solute particles and solvent molecules. When a solute dissolves, it undergoes two main steps: breaking the solute-solute bonds and breaking the solvent-solvent bonds. These steps require energy input. Subsequently, solute particles interact with solvent molecules, forming new solute-solvent bonds, which releases energy. The overall solvation enthalpy is the net result of these energy changes.

A negative solvation enthalpy indicates an exothermic process, meaning that the energy released during the formation of solute-solvent interactions is greater than the energy required to break the solute-solute and solvent-solvent bonds. This typically leads to spontaneous dissolution. Conversely, a positive solvation enthalpy signifies an endothermic process, where more energy is absorbed than released, and dissolution may require external energy input or might not occur spontaneously. The magnitude and sign of the solvation enthalpy depend on the nature of the solute and solvent, including their polarity, intermolecular forces, and ionic character. For ionic compounds, this enthalpy change is often referred to as hydration enthalpy when the solvent is water.