Voltammetric Analyzer—The Instrumentation

The excitation signal ( appi) is simultaneously applied across the working and reference electrode. The reference electrode circuit contains a large resistance ( 1011 ft) such that, practically speaking, no current is present in the electrode, 

Electrode type Properties (V vs SCE) Approximate useful range 

Glassy carbon Are chemically resistant, highly conductive, and mechanically rigid 1 M HCIO4 (0 to + 1.8) 

Commonly used reference electrodes, along with the reactions responsible for generating the reference potential and their potential values vs the normal hydrogen electrode (NHE) are given below. The reference electrode potential must be added to the experimentally observed value when reporting a value vs NHE. 

For the silver-silver chloride electrode, equations (A.2.7)-(A.2.8), /i rei depends on [Cl-] in the electrolyte (3 M NaCl) the electrolyte should be replaced every once in a 

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