Sodium chloride has a low solubility in alcohol, and the polarity of ethanol is also less than that of water. It is weak in cooperation with solvated water of sodium chloride. Therefore, sodium chloride is difficult to ionize free ions in ethanol, but it is an ion after all. Compounds are not simple molecules, so they should be considered as ion pair forms. Because the ionic bonds are not saturated, the formed ion pairs can also attract each other to form large aggregates by electrostatic interaction between different poles, and the particle size can reach colloidal particles. The scale range. While the strong polar compound water and sodium chloride have a strong solvation effect, the sodium chloride is completely ionized and the free hydrated ions are highly dispersed, wherein the hydrated ion has a particle size smaller than the colloidal range and belongs to the solution.