Theory of the Ultrasonic Absorption in Aqueous Solutions (II) Aqueous Solutions of Some Alcohols

Anomalous parts of the ultrasonic absorption coefficient have been calculated for aqueous solutions of methanol, ethanol and n -propanol as functions of the concentration by employing the result of the general theory described in part (I) of this paper (J. Phys. Soc. Japan 11 (1956) 827), which is based on the assumption that the pressure change of the sound wave accompanies a change in the existence ratio between the single and the associated molecules of water, that there takes place a molecular rearrangement among the single and the associated molecules of water and the solute molecules, accompanying changes in configurational entropy of the system, and that the irreversible entropy production takes place in the stage of energy transfer from the thermal motion to the configurational degree of freedom and vise versa. Calculations have been performed for two simplified model cases: (a) ignoring the difference in sizes of the single water molecule and the solute molecule, and (b) taking into account the d...