Our Gaussian process model is trained to predict microscopic pK a s which can be used to analytically calculate macroscopic pK a s. Most experimentally measured pK a s are macroscopic, providing an equilibrium constant for an overall change in total charge. These macroscopic transitions are comprised of multiple microscopic transitions, each of which consists of the removal of one specific hydrogen atom. If pK a s, or equilibrium constants, for all microscopic transitions are known, then the macroscopic pK a can be analytically calculated using a thermodynamic cycle . For example, for a molecule with two ionizable groups, the macroscopic K a 's are: