The concentration of a certain metal ion in a given water sample can be determined using voltammetry through the following steps:1. Sample preparation: First, collect the water sample and filter it to remove any suspended particles. The sample may need to be acidified to ensure that the metal ions are in a suitable oxidation state for analysis.2. Electrode preparation: Choose a suitable working electrode, such as a glassy carbon electrode or a mercury-based electrode, depending on the metal ion of interest. Clean and polish the electrode to ensure a reproducible surface.3. Voltammetric analysis: Set up the electrochemical cell, which typically consists of a working electrode, a reference electrode e.g., Ag/AgCl or saturated calomel electrode , and a counter electrode e.g., platinum wire . Connect the electrodes to a potentiostat, which controls the applied voltage and measures the resulting current.4. Perform a voltammetric technique, such as linear sweep voltammetry, cyclic voltammetry, or differential pulse voltammetry, to obtain a voltammogram. The voltammogram will display the current response as a function of the applied voltage. The metal ion of interest will produce a characteristic peak at a specific voltage, corresponding to its reduction or oxidation.5. Calibration: Prepare a series of standard solutions containing known concentrations of the metal ion. Analyze these standards using the same voltammetric technique and conditions as the water sample. Plot the peak current response versus the metal ion concentration to generate a calibration curve.6. Determine the concentration: Measure the peak current response for the water sample and use the calibration curve to determine the concentration of the metal ion in the sample.The sensitivity and limit of detection LOD of the voltammetric method depend on the specific technique used, the electrode material, and the metal ion being analyzed. Generally, voltammetric methods have high sensitivity, with LODs in the nanomolar to picomolar range. However, these values can vary depending on the experimental conditions and the nature of the analyte. To improve the sensitivity and LOD, various modifications can be made, such as using more sensitive electrodes, optimizing the voltammetric technique, or employing pre-concentration methods.