9.6.A—Explain the relationship between the solubility of a salt and changes in the enthalpy and entropy that occur in…

Explain the relationship between the solubility of a salt and changes in the enthalpy and entropy that occur in the dissolution process.

• The free energy change (ΔG°) for dissolution of a substance reflects a number of factors: the breaking of the intermolecular interactions that hold the solid together, the reorganization of the solvent around the dissolved species, and the interaction of the dissolved species with the solvent. It is possible to estimate the sign and relative magnitude of the enthalpic and entropic contributions to each of these factors. However, making predictions for the total change in free energy of dissolution can be challenging due to the cancellations among the free energies associated with the three factors cited.