《POLAROGRAPHIC TECHNIQUES》

Ⅰ.The Nature and Scope of Polarographic Measurements1

Ⅱ.Instrumentation7

1.Polarographic Circuits7

2.Polarographic Cells18

3.Dropping Electrode Assemblies.Fabrication and Maintenance of the Capillary27

4.Auxiliary Equipment32

Ⅲ.The Polarographic Limiting Current39

1.The Residual Current39

2.The Migration Current42

3.Theory of the Diffusion Current45

4.Factors Affecting the Diffusion Current48

A.The Concentration of Reducible Substance48

B.The Capillary Characteristics.Factors Affecting m and t51

C.Temperature55

D.Solvent Composition57

E.Polarographic Diffusion Coefficients59

5.Methods of Measuring the Diffusion Current60

6.Estimation of n from Diffusion Current Data71

7.Kinetic Currents77

8.Catalytic Currents78

9.Adsorption Waves82

Experiments84

Ⅳ.Theory of the Current-Voltage Curve93

1.Reduction to a Metal Soluble in Mercury93

2.Reduction or Oxidation to a Solid Phase Insoluble in Mercury98

3.Homogeneous Electrode Reactions99

4.Criteria of Reversibility104

5.The Interpretation of Irreversible Waves109

Experiments110

Ⅴ.The Interpretation of Half-Wave Potential Data115

1.Effect of Complex Formation on E1/2 for a Heterogeneous Electrode Reaction115

2.Interpretation of the Half-Wave Potential for a Homogeneous Electrode Reaction120

3.Summary of Factors Attecting the Half-Wave Potential123

4.Qualitative Polarographic Analysis126

Experiments127

Ⅵ.Maxima and Their Suppression131

1.The Nature of Maxima and Their Significance in Practical Work131

2.Maximum Suppressors135

3.Some Undesirable Effects of Maximum Suppressors139

Experiment141

Ⅶ.Techniques of Quantitative Polarographic Analysis143

1.Isolation of the Wave143

A.General Considerations143

B.Selection of the Medium144

C.Non-linear Wave Height-Concentration Relationships157

D.Indirect Methods of Analysis159

2.Special Techniques for Unstable Solutions162

A.Solutions which React with Components of the Salt Bridge162

B.Solutions of Strong Oxidizing Agents163

C.Solutions of Strong Reducing Agents165

3.Separations Preceding Polarographic Analysis167

A.Precipitation168

B.Extraction169

C.Chemical Reduction169

D.Electrolytic Reduction170

4.The Interpretation of the Wave Height172

A.Absolute Methods173

B.Comparative Methods175

Experinents181

Ⅷ.Amperometric Titrations185

1.Types of Amperometric Titrations and the Corresponding Current-Volume Curves185

A.Precipitation Titrations185

B.Redox Titrations189

C.Complex-formation Titrations193

D.“Compensation”Titrations193

2.Technique and Apparatus195

3.Rotating Platinum Microelectrodes198

Experiments200

Ⅸ.Special Techniques205

1.Controlled Potential Electrolysis205

2.Coulometry at Controlled Potential217

3.Millicoulometry221

4.Other Polarographic Current-Time Curves224

5.Derivative Polarography226

Literature Cited229

Appendix A.Trouble-Shooting in Polarographic Circuits235

Appendix B.Half-Wave Potentials and Diffusion Current Constants of Inorganic Substances247

Index309