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What is the concentration of chloride ions in a sample of seawater using potentiometry, if a 0.1 M silver nitrate solution is used as a titrant and a silver-silver chloride electrode is used as an indicator electrode?

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To determine the concentration of chloride ions in a sample of seawater using potentiometry, you need to perform a titration with a known concentration of silver nitrate solution  0.1 M  and use a silver-silver chloride electrode as an indicator electrode. Here's a step-by-step guide on how to do this:1. Prepare the sample: Collect a known volume  V1  of the seawater sample and place it in a titration vessel.2. Prepare the titrant: Fill a burette with the 0.1 M silver nitrate solution.3. Set up the potentiometer: Connect the silver-silver chloride electrode to a potentiometer or a pH meter capable of measuring millivolts.4. Begin the titration: Slowly add the silver nitrate solution from the burette to the seawater sample while stirring. Monitor the potential  voltage  change on the potentiometer.5. Endpoint detection: As you add the silver nitrate, the potential will change. When the potential change becomes minimal or starts to level off, you have reached the endpoint of the titration. At this point, all the chloride ions have reacted with the silver ions to form silver chloride precipitate.6. Record the volume: Note the volume  V2  of the silver nitrate solution used to reach the endpoint.7. Calculate the concentration of chloride ions: Use the following equation to determine the concentration of chloride ions in the seawater sample:AgNO3  aq  + Cl-  aq   AgCl  s  + NO3-  aq Since the stoichiometry of the reaction is 1:1, the moles of chloride ions are equal to the moles of silver nitrate used in the titration:moles of Cl- = moles of AgNO3To find the moles of AgNO3, use the formula:moles = Molarity  Volumemoles of AgNO3 = 0.1 M  V2  in liters Now, to find the concentration of chloride ions in the seawater sample, divide the moles of chloride ions by the initial volume of the seawater sample:Concentration of Cl-  M  = moles of Cl- / V1  in liters By following these steps and calculations, you can determine the concentration of chloride ions in the seawater sample using potentiometry.

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