Potentiometry is an electrochemical technique used to determine the concentration of ions in a solution by measuring the potential difference voltage between two electrodes. To determine the concentration of chloride ions in a sample of pool water, you can use a potentiometric titration with a silver nitrate AgNO3 solution as the titrant and a silver/silver chloride Ag/AgCl electrode as the indicator electrode. The following steps outline the procedure:1. Prepare the sample: Collect a representative sample of pool water in a clean beaker or container. You may need to filter the sample to remove any suspended particles or debris.2. Calibrate the pH meter: Before starting the titration, calibrate the pH meter using standard buffer solutions to ensure accurate measurements.3. Prepare the titrant: Prepare a standard solution of silver nitrate AgNO3 with a known concentration. This will be used as the titrant to react with the chloride ions in the pool water sample.4. Set up the titration apparatus: Place the pool water sample in a beaker or flask and insert the Ag/AgCl indicator electrode and a reference electrode e.g., a saturated calomel electrode into the solution. Connect the electrodes to a pH meter or a potentiometer.5. Perform the titration: Slowly add the AgNO3 solution to the pool water sample while continuously stirring the solution. Monitor the potential difference voltage between the two electrodes using the pH meter or potentiometer. The potential difference will change as the AgNO3 reacts with the chloride ions in the sample.6. Determine the endpoint: The endpoint of the titration is reached when the potential difference between the electrodes suddenly changes, indicating that all the chloride ions have reacted with the AgNO3. This is known as the equivalence point.7. Calculate the concentration of chloride ions: Using the volume of AgNO3 solution added at the endpoint and its known concentration, you can calculate the concentration of chloride ions in the pool water sample using the stoichiometry of the reaction:AgNO3 + Cl- AgCl s + NO3-Since the reaction between AgNO3 and Cl- is a 1:1 reaction, the moles of Cl- in the sample are equal to the moles of AgNO3 added at the endpoint. Divide the moles of Cl- by the volume of the pool water sample to obtain the concentration of chloride ions.By following these steps, you can use potentiometry to determine the concentration of chloride ions in a sample of pool water.