You work for a laboratory that undertakes analyses of a range of samples (food, drinking water and treated industrial wastewater) for external clients. The samples are analysed for a suite of trace metal contaminants including Pb, Cd, Fe, Mn, Zn, Hg, Cu and other metals on request. The manager of the laboratory is considering adding two electrochemical techniques to your suite of analyses and has asked you to do some background research. For each of the techniques listed below prepare a summary suggesting why each technique should be considered, how it could be applied and any potential disadvantages to the system. Ensure you reference your sources properly. Potentiometric titrations Polarography with dropping mercury electrode.