Theoretical Background Linking Electrochemistry to Electrochemical Detection

2 Theoretical Background Linking Electrochemistry to Electrochemical Detection 

Faraday s Law states that the amount of substance consumed or produced at one of the electrodes in an electrolytic cell is directly proportional to the amount of electricity that passes through the cell . 

Since the current is formed from an electroactive chemical dissolved in the solution interacting with the adjacent electrode surface, it is not surprising that the probability of a molecule or ion reacting at the electrode surface is directly related to its concentration. Therefore, current density (i.e. current/electrode area) is normally directly proportional to analyte concentration. When all the analyte in a solution is electrolysed at an electrode then according to Faraday s Law, the measurable response is directly related to the molar amount of analyte  

Thus the Faraday constant is the charge on die electron multiplied by Avogadro s number. By definition, an electrical current (i), measured in amperes (A), is determined as coulombs per second  

Equation 2.5 shows that the rate at which electrons are moved across the electrode-solution interface (i.e. the current) is directly related to the rate of 

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