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What is the concentration of chloride ions in a given sample of seawater using coulometry?

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To determine the concentration of chloride ions in a given sample of seawater using coulometry, you will need to follow these steps:1. Collect a known volume of the seawater sample.2. Perform a coulometric titration using a suitable titrant, such as silver ions  Ag+ , which will react with chloride ions  Cl-  to form a precipitate of silver chloride  AgCl . The reaction can be represented as:   Ag+ + Cl-  AgCl s 3. Set up the coulometric titration apparatus, which includes a generator electrode  anode  where the titrant is generated, a counter electrode  cathode , and a reference electrode. The generator electrode is typically made of silver, and the titrant  Ag+  is generated by oxidizing the silver electrode.4. Record the initial coulombs  Q1  before starting the titration.5. Start the titration and monitor the current  I  and time  t  during the titration. The current should be kept constant throughout the titration.6. Stop the titration when the endpoint is reached. This can be detected by a sudden change in potential or by using an appropriate indicator, such as a chloride ion-selective electrode.7. Record the final coulombs  Q2  after the titration is complete.8. Calculate the total coulombs consumed during the titration  Q  using the formula:   Q = Q2 - Q19. Use Faraday's law of electrolysis to determine the moles of chloride ions titrated:   n Cl-  = Q /  F * z    where n Cl-  is the moles of chloride ions, Q is the total coulombs consumed, F is Faraday's constant  approximately 96485 C/mol , and z is the charge of the chloride ion  1 for Cl- .10. Calculate the concentration of chloride ions in the seawater sample:   [Cl-] = n Cl-  / V_sample   where [Cl-] is the concentration of chloride ions and V_sample is the volume of the seawater sample.By following these steps, you can determine the concentration of chloride ions in a given sample of seawater using coulometry.
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