Joint Redox Mechanism of Water Synthesis in H₂ and O₂ Mixture in the Presence of a Series of Metal Oxides

Abstract—This article describes a joint redox mechanism that, using the example of water synthesis in the presence of certain metal oxides, explains the important thermodynamic features of this mechanism. This study is based on a comparison of the total enthalpy of the formation of Δ_fH_T redox reaction components with the reaction energy E spent when its temperature rises. Taking into account the number of moles of the resulting products of the reduction-oxidative reaction (atoms and molecules), the reaction mode (equimolar and isobaric), and the law of conservation of energy, these values should be equal. Analysis of a number of reactions differing in metal oxides (Ag₂O, NiO, PtO₂) and reducing gases (H₂, CO, SO₂), taking into account some self-cooling of the oxides during their reduction confirmed these expectations. The theoretical estimates are in reliable agreement with the experimental data. As a result of our research, the 200-year-old mystery of water synthesis, described by Sir Humphrey Davy in 1817, was solved by us based on the modern physicochemical concepts, not related to catalysis.