In this context, X(s) and X(aq) represent compounds in the solid and aqueous phases, respectively, which have an equilibrium constant of K solv (solvation process). Furthermore, solvated species can increase their solubility by undergoing either an acid-base reaction or salt dissociation/formation, ultimately reaching equilibrium defined by K eq . X(s) is chargeneutral (q = 0). If the molecule of interest is charged (e.g., Z ∓ ), a counterion (C ± ) is needed to stabilize the crystal. Y ±n denotes the (de)protonated form of X.