Determination of the enthalpy of solution of salts

When a salt is dissolved in water, it can heat the solution up or cool it down. Accordingly, the enthalpy of solution is either negative (heat generating) or positive (heat absorbing). For the dissolution of the crystal, the so-called lattice energy must be applied. In hydration, on the other hand, energy is released. Enthalpies of solution cannot be calculated with certainty, but rather must be determined experimentally.

Experiment C1.7.3.1 determines the enthalpy of solution of various chloride salts. For this purpose, the salts LiCl, KCl and NaCl are dissolved in the transparent demonstration Dewar flask. The enthalpy of solution can then be calculated from the temperature change.