We present an efficient scheme for combining ab initio calculated solid states with experimental aqueous states through a framework of consistent reference energies. Our work enables accurate prediction of phase stability and dissolution in equilibrium with water, which has many important application areas. We formally outline the thermodynamic principles of the scheme and show examples of successful applications of the proposed framework on 1) the evaluation of the water-splitting photocatalyst material Ta3N5 for aqueous stability 2) the stability of small nano-particle Pt in acid water 3) the prediction of particle morphology and facet stabilization of olivine LiFePO4 as a function of aqueous conditions.