A.C. polarographic studies on the influence of tensammetric waves on reduction peaks of inorganic cations and vice versa

This investigation deals with the studies on the effect of the nature and concentration of surface active substances (s.a.s) on the a.c. reduction peaks of Cd3+ and Zn3+ ions and vice-versa by a.c. polarography. The magnitude of the reduction peak is not influenced up to a certain concentration of the s.a.s., but with concentrations higher than this, the magnitude of the reduction peak progressively decreases; a concentration of 1.3% of n-amyl alcohol completely removes the 10−3M Cd2+ peak. Neither magnitude nor the peak potential of the tensammetric peak of n-amyl alcohol are influenced by the presence of Cd2+ ions. There is a linear relation between the concentration of the electroactive species and the optimum concentration of the s.a.s., and also the concentration of the s.a.s. just required to remove the reduction peak. These observations are further supported by the curve which gives the linear relation between the concentration of the electroactive species and the amount of the s.a.s. required to reduce the magnitude of the reduction peak to half its value. The amount of the surfactants required to remove the reduction peak completely is in the order n-amyl alcohol > Cerfak [sodium napthalene (2-dodecyl)3-sulphonate] > cetylpyridinium bromide. These results are discussed.