determine the concentrated of mohrs salt solution with the help of supplied n/10 kmno4 solution preparred?
To determine the concentration of a Mohr's salt (FeSO4(NH4)2SO4.6H2O) solution using a supplied N/10 KMnO4 (potassium permanganate) solution, you can follow these steps:
1. Prepare a standard solution of Mohr's salt by dissolving a known mass of the salt in distilled water in a volumetric flask. Make sure to accurately record the mass used and the volume of the flask.
2. Take a specific volume (e.g., 25 mL) of the Mohr's salt solution using a pipette and transfer it into a conical flask.
3. Add a few drops of dilute sulfuric acid (H2SO4) to the conical flask. This acidifies the solution and prevents the precipitation of any other metal ions.
4. Titration setup: Take the supplied N/10 KMnO4 solution in a burette. Note the initial burette reading. The KMnO4 solution acts as the titrant.
5. Start the titration by adding KMnO4 solution drop by drop into the conical flask containing Mohr's salt solution. The reaction between the Mohr's salt and KMnO4 proceeds as follows:
5FeSO4(NH4)2SO4.6H2O + 2KMnO4 + 8H2SO4 -> 5Fe2(SO4)3 + 2MnSO4 + K2SO4 + 2(NH4)2SO4 + 8H2O
6. The solution in the conical flask will turn pink due to the excess KMnO4. Continue adding the KMnO4 solution until a permanent pink color is obtained. At this point, the reaction is complete.
7. Record the final burette reading and calculate the volume of KMnO4 solution required for the reaction.
8. Now, use the calculated volume of KMnO4 solution and its concentration (N/10) to determine the number of moles of KMnO4 used.
9. Since the stoichiometry of the reaction is 1:1 between FeSO4 (Mohr's salt) and KMnO4, the number of moles of KMnO4 used is equivalent to the number of moles of FeSO4 in the solution.
10. Finally, calculate the molar concentration of Mohr's salt by dividing the number of moles of FeSO4 with the volume of the Mohr's salt solution used in the titration.
Remember to perform the titration carefully, ensuring accurate readings and precise measurements.