Peculiar Points of Aqueous Solutions of Mono-Hydrogen Alcohols

The work is devoted to the detailed study of the peculiar points in aqueous solutions of mono-hydrogen alcohols. The main attention is focused on water-methanol and water-ethanol solutions for which there are numerous experimental data. It is taken into account that H-bond interaction between alcohol and water molecules stimulates the formation of hydration complexes or elementary clusters, stable for temperatures: T < 42 degrees C. A solution at the peculiar point has a cell-like structure, where every cell consists of one alcohol molecule surrounded by water molecules forming mono-molecular layer. The volume and dissolution heat per cluster are determined. It is shown that the peculiar point arises at the concentration leading to the full filling of a solution by elementary clusters. The instability of elementary clusters near the peculiar point is considered. The possible existence of peculiar point of another type is discussed. (C) 2022 Elsevier B.V. All rights reserved.