Determination of Copper and Faraday’s Constant using a simple Electrochemical Cell

This experiment was designed for use in Quantitative Analysis to demonstrate the applicability of the Nernst equation for quantitative determination of an analyte, while also laying the groundwork for future studies of the essentials of instrumentation. A simple electrochemical cell made using a commercially available H-cell, a silver-silver chloride reference electrode, and an inexpensive copper wire as an indicator electrode allows students to experimentally determine both the concentration of aqueous copper(II) ion and Faraday’s constant. A calibration curve is made by plotting the Nernst equation, reinforcing the connection between theoretical construct and practical application. The experimentally determined Faraday’s constants typically show between 10 to 50% error from the literature value, offering opportunity to explore properties of electrodes that cause deviation from the expected value. While several examples of Nernst equations with silver analytes are available in the literature, this experiment offers fast analysis and an economical alternative.