Exhaustive oxidation-reduction of nitrite, nitrate and hydrazine was achieved by application of a square wave potential regime to a platinum electrode. The parameters of the square wave were chosen after investigation of the adsorption behaviour of the three compounds. The three compounds were found to adsorb and desorb at a platinum electrode in the potential window from -0.2 V to 1.3 V and hence the lower potential of the square wave was -0.2 V while the upper potential was 1.3 V. The square wave was applied to a solution containing the test compound for 10 h. The results of analysis indicated a decrease in the concentration of the tested compounds with respect to the control sample. The optimal frequencies for the conversion were 10, 50 and 10 for nitrite, nitrate and hydrazine, respectively. Analysis of solutions for possible products of the exhaustive oxidation gave negative tests for NO2-, NO3-, and NH3 leaving the possibility of conversion to nitrogen as the end product.