To determine the concentration of lead Pb ions in a water sample using voltammetry with a reference electrode, you will need to follow these steps:1. Prepare the water sample: Collect a representative water sample and filter it to remove any particulate matter. You may also need to acidify the sample to stabilize the lead ions.2. Set up the voltammetry equipment: This includes a working electrode usually a glassy carbon or mercury electrode , a reference electrode such as Ag/AgCl or saturated calomel electrode , and a counter electrode usually platinum . Connect these electrodes to a potentiostat, which controls the voltage applied to the working electrode.3. Perform the voltammetry experiment: Apply a potential to the working electrode and sweep the potential in a specific range. As the potential changes, the current response at the working electrode will be measured. The current response is related to the concentration of the analyte in this case, lead ions .4. Analyze the voltammogram: The voltammogram is a plot of current vs. potential. The peak current in the voltammogram corresponds to the reduction or oxidation of the lead ions at the working electrode. The position of the peak potential can be used to confirm the identity of the analyte lead ions , while the peak current is proportional to the concentration of lead ions in the sample.5. Calibration: To determine the concentration of lead ions in the sample, you will need to create a calibration curve. This involves running voltammetry experiments with known concentrations of lead ions and plotting the peak current vs. concentration. You can then use this calibration curve to determine the concentration of lead ions in your unknown sample based on its peak current.6. Calculate the concentration: Using the calibration curve, determine the concentration of lead ions in the water sample based on the peak current observed in the voltammogram.Keep in mind that the accuracy and precision of this method depend on various factors, such as the quality of the electrodes, the cleanliness of the sample, and the calibration curve's linearity. Additionally, interferences from other electroactive species in the sample may affect the results.