Unified pH Measurements of Ethanol, Methanol, and Acetonitrile, and Their Mixtures with Water.

Measurement of pH in aqueous-organic mixtures with different compositions is of high importance in science and technology, but it is, at the same time, challenging both from a conceptual and practical standpoint. A big part of the difficulty comes from the fundamental incomparability of conventional pH values between solvents (pH, solvent-specific scales). The recent introduction of the unified pH (pH) concept opens up the possibility of measuring pH, expressed as pHabsH2O, in a way that is comparable between solvent, and, thereby, removing the conceptual problem.