Influence of ultrasonic waves on tellurium hydrosol

Abstract

The influence of ultrasonic waves (1 Mc/s 225 watts per sq. cm. electrical output to the transducer) on tellurium hydrosol prepared by the reduction of telluric acid with hydrazine hydrate has been studied in this paper. It is observed that the colloidal phase of the sol disappears on exposing the sol for three hours. The specific conductivity and hydrogen ion concentration shows a continuous increase with the time of exposure to ultrasonic waves. The colour of the sol changes from bluish-brown to colourless. The effect of hydrogen peroxide on the sol is also studied. The sol becomes unstable as soon as the stabilising tellurate and tellurite ions are rendered free under the action of ultrasonic waves. In presence of non-electrolytes as ethyl alcohol and acetone, the sol becomes stable to the action of ultrasonic waves. The changes in hydrogen ion concentration and specific conductivity become small. The colloidal phase does not disappear in three hours of exposure to ultrasonic waves.