The present work deals with evaluation of different configurations of sonochemical reactors using a model reaction with justification on the basis of cavitational activity predictions of theoretical simulations. In addition, intensification of the cavitational effects using additives has been investigated and its dependency on the inherent cavitational activity in the reactor has been established. The model reaction used for experimental investigations is the potassium iodide oxidation, also known as the Weissler reaction whereas the theoretical prediction of cavitational activity has been achieved using the numerical simulations of the sound wave equation using Comsol Multi physics software. The effects of various additives for enhancing the cavitational activity such as solid particles like cupric oxide, salts like sodium nitrite and radical promoters such as ferrous sulphate have also been investigated. It has been observed that the configuration with higher transducer areas gives better distribution of the cavitational activity and also gives enhanced effects as quantified using the cavitational yield measurements. Also it has been conclusively established that depending on the mechanism of intensification, the beneficial effects obtained using different additives are strongly dependent on the inherent cavitational activity which in turn depends on the type of reactor and the operating conditions. (C) 2011 Elsevier B.V. All rights reserved.