ON THE RELATIONSHIP BETWEEN INTERNAL PRESSURE AND ULTRASONIC VELOCITY

Abstract

Because of the relevance of internal pressure data to sonochemical kinetics, some interest attaches to expressions which permit evaluation of P i from readily available or easily measured quantities. One such expression is developed in this paper. It relates P i to the velocity u of ultrasonic waves transmitted through the liquid and takes the form u√D = K′√(R m )Pi where K′ is a constant proportional to √(Cp/C v )√(1/RT), and D and R m denote the density and molar refraction of the liquid.The utility of this expression is tested against some 100 liquids (including a few binary liquid mixtures and aqueous electrolyte solutions), and it is shown that the equation offers an acceptable and quite general method for calculating P i .