Hofman, David Lester2015-08-062015-08-062015-08-06http://hdl.handle.net/10539/18189A Dissertation Submitted to the Faculty of engineering University of the Witwatersrand, Johannesburg for the Degree of Master of Science in Engineering Johannesburg 1984The rate of mass transfer at gas evolving electrodes has been shown to be a strong function of the so-called bubble break off diameter of the gas bubbles leaving the electrode surface. This dissertation shows how the population balance can be applied to the formation of gas bubbles at gas evolving electrodes. This analysis provides a means of predicting the bubble break off aiameter. Experiments were also performed to measure the bubble break off diameter as well as other parameters, such as the rate of bubble growth, used in the population balance moce-i>. The effect of viscosity, electrolyte flowrate and current on the bubble break off diameter is also investigated. The flowrate and current have little effect on the bubble bi ak off diameters, whi.e the break - - - diameters show a decrease in size with increasing viscosity. The bubble break off diameters predicted by the population balance mode, and those measured were significantly larger than those reported in the literatureenGas dynamicsThesis