Velocity of Sound in Pure Liquids and Liquid Mixtures

The velocity of sound was expressed in terms of internal energy and some physical constants, and an equation was derived to calculate the velocity of sound in pure liquids and liquid mixtures. Acoustical velocities were calculated for a number of binary mixtures of organic liquids and compared with experimental data. The observed variation of sound velocities with concentration was explained. The agreement between the theory and the experiment is quite satisfactory. The sound velocity equation was used to calculate the velocity of sound in aqueous solutions of electrolytes. The values predicted by theory are in good agreement with the experimental data. These values were used to determine the adiabatic compressibility for aqueous solutions of various alkali halides. Some conclusions were drawn concerning the acoustical properties of electrolyte solutions and the possibilities of applying acoustic measurements to calculation of various physico‐chemical data.