Analytical Chemistry

solution is undesirable, or for non-aqueous titrations where a calomel or silver–silver chloride reference electrode may become ...

Instrumentation Micro-electrode (dropping mercury carbon or platinum), reference electrode, variable dc source, electronics and ...

Figure 6.9 Polarographic wave or polarogram. material. In each polarographic wave, the potential at which the diffusion current ...

Half-wave Potentials Electroactive species are characterized by their E1/2 values which are constants related to the standard el ...

Figure 6.10 Dropping mercury electrode. that it is essential to control the cell temperature to ± 0.1 K if the highest precision ...

Oxygen Waves Two waves caused by the reduction of dissolved oxygen can interfere with the waves of other electroactive species u ...

Figure 6.11 Oscillographic polarography. (a) Variation of drop area and applied potential with time. (b) Oscillographic display ...

Figure 6.12 Timing sequence for differential pulse polarography (left) and resulting differential polarogram (right). electrode ...

Figure 6.13 (a) Apparatus for stripping analysis. (b) Curve A: Current–voltage curve for anodic stripping of cadmium. Curve B: R ...

anode and a silver cathode. In an alkaline electrolyte (e.g. 1 M KOH) the following reaction will occur if a reducible species i ...

compound. Oxidases require oxygen to react, and so decrease the amount of oxygen in their immediate environment. The degree of o ...

Figure 6.15 Amperometric titration curves. (a) Only substance titrated is reducible, e.g. Pb2+ against , Ag+^ against halide. (b ...

(1) Both reactants behave reversibly. The curve is as shown in Figure 6.16(a) and is exemplified by the titration of Fe(II) with ...

can act as its own supporting electrolyte. Reducible anions such as can also be determined provided solutions are well buffered. ...

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only one or two metals present. Selective deposition of metals from multi-component mixtures can be achieved by controlling the ...

constant potential, in which case the current diminishes to zero as the reaction goes to completion, or at constant current. The ...

Figure 6.17 Circuit diagram for coulometric titrations. The titrant is usually generated directly in the solution whence it can ...

Applications of Coulometric Titrations The coulometric generation of titrants is widely applicable to redox, precipitation, acid ...

Disadvantages Conductance is a non-specific property; high concentrations of other electrolytes can be troublesome. The electric ...