Particular points of water-alcohol solutions

The paper discusses the physical nature of the nontrivial properties of aqueous alcohol solutions in a range of molar concentrations x ∼ 0.05. A particular point is determined based on analysis of the temperature and concentration dependences of contraction, which is the simplest thermodynamic characteristic of solutions. The occurrence of particular points in water-alcohol solutions is shown to be directly related to the structural features of water. The concentration-temperature dependence is plotted, where the contraction behavior of an aqueous ethanol solution demonstrates a structural feature of water. The formulas to find the concentration values at particular points are proposed.