Messung und Deutung der Konzentrationsabhängigkeit der Ultraschall-absorptioh wäßriger CoSO₄-Lösungen im Frequenzbereich 0,2 bis 2 MHz

An apparatu s for the exact determination of small ultrasonic absorption coefficients (order of magnitude α = 0,01dB/cm ) in liquids is described. Experimental results of the ultrasonic absorption of aqueous solutions of CoS0₄ at 20°C in the range of concentrations from 0,025 to 2,2 mole/liter and at frequencies ranging from 0,2 to 2 Mc/s are reported. In this frequency range the molecular ultrasonic absorption per wavelength referred to one CoS0₄-molecule passes through a maximum. The dependence on concentration of the maximum absorption per wavelength, and of the respective relaxation times, was found to follow simple mathematical laws. These are valid at concentrations almost up to saturation with CoS0₄. A quantitative interpretation of the experimental results is discussed under the assumption of a dissociation reaction consisting of several stages.