Standarisasi Perak Nitrat dengan NaCl Metode Titrasi Argentometri (Mohr)

Introduction

This tutorial will guide you through the process of standardizing silver nitrate (AgNO3) using sodium chloride (NaCl) through the Mohr titration method. This technique is essential in analytical chemistry for determining the concentration of silver nitrate in a solution. By following these steps, you will gain hands-on experience in titration and enhance your laboratory skills.

Step 1: Prepare Sodium Chloride Standard

• Weigh the NaCl
  • Use an analytical balance to accurately weigh the required amount of NaCl.
  • Ensure that the balance is calibrated and that you tare the weighing container before adding NaCl.
• Dissolve in Distilled Water
  • Place the weighed NaCl in a clean volumetric flask.
  • Add distilled water to dissolve the salt completely, ensuring the final volume is accurate (typically 1 liter).

Step 2: Set Up the Titration Process

• Gather Equipment
  • You will need a burette, Erlenmeyer flask, pipette, and a white tile (to better observe color changes).
• Fill the Burette
  • Fill the burette with the silver nitrate solution. Make sure there are no air bubbles in the tip.
• Pipette the NaCl Solution
  • Use a pipette to transfer a measured volume of the NaCl standard solution into the Erlenmeyer flask.

Step 3: Conduct the Titration

• Add Indicator
  • Add a few drops of chromate indicator to the NaCl solution in the flask. This will help visualize the endpoint of the titration.
• Titrate
  • Slowly open the burette to allow silver nitrate to flow into the flask while continuously swirling the flask.
  • Observe the color change: the solution should change from yellow to a reddish-brown at the endpoint, indicating the presence of silver chromate.

Step 4: Record and Calculate Results

• Document Volume Used

  • Note the initial and final readings of the burette to determine the volume of silver nitrate used in the titration.

• Perform Calculations

  • Use the titration data to calculate the concentration of the silver nitrate solution using the formula:

  [ C_1V_1 = C_2V_2 ]

  Where:

  • ( C_1 ) = concentration of NaCl
  • ( V_1 ) = volume of NaCl used
  • ( C_2 ) = concentration of AgNO3
  • ( V_2 ) = volume of AgNO3 used

Conclusion

In this tutorial, you learned how to standardize silver nitrate using the Mohr titration method with sodium chloride. This process involved preparing a NaCl standard, setting up the titration apparatus, conducting the titration, and calculating the concentration of silver nitrate. Mastering this technique is beneficial for various applications in analytical chemistry and laboratory practices. For further learning, consider exploring additional titration methods and their applications.