Oxidation Titration
Introduction/Theoretical Background: A common task in chemistry is the determination of a substance present in a product. If the product contains a substance that can be oxidized, then it is possible to determine the number of moles of that substance by titrating the sample with a solution of a strong oxidizing agent. In this lab, a solution of KMnO4, an oxidizing agent, will be standardized by titration with a solution containing a known concentration of iron (II) ions, (Fe+). The concentration of oxalic acid solution will be determined by titration with the MnO4- solution that had been standardized first. The purpose of this lab is to standardize a solution of potassium permanganate by redox titration with a standard solution of iron (II) ions. A solution of oxalic acid is then titrated with the permanganate solution to determine the exact concentration of oxalic acid.
Purpose:
The purpose of the experiment was to use the permanganate ion, a strong oxidizing agent, in a titration in order to determine the concentration of a FeSO4 solution. Purple MnO4- ion from a standardized potassium permanganate solution was titrated thrice to give clear Mn2+ with an analyte of acidified FeSO4 until all the Fe2+ in the solution was oxidized to Fe3+. The color of the MnO4-/Mn2+ was used as the indicator for the titration. A balanced oxidation-reduction, the molarity/normality of the standards potassium permanganate, and the volume of potassium permanganate used allowed the determination of the concentration of the FeSO4.
Equipment and Chemicals:
Chemicals:
* Iron (II) ammonium sulfate solution, Fe(NH4)2∙6H2O, 0.100 M, 50 mL
* Manganese sulfate solution, MnSO4∙ H2O, 1.0 M, 50 mL
* Oxalic acid solution, H2C2O4, 0.25 M, 60 mL
* Potassium permanganate solution, KMnO4, approx. 0.02 M, 100 mL
* Sulfuric acid solution, H2SO4, 6 M, 50 mL
Materials:
* Buret, 50-mL
* Erlenmeyer flasks, 250-mL, 3
* Hot plate
* Thermometer
* Volumetric pipet, 10-mL
* Volumetric pipet, 25-mL
*
Purpose:
The purpose of the experiment was to use the permanganate ion, a strong oxidizing agent, in a titration in order to determine the concentration of a FeSO4 solution. Purple MnO4- ion from a standardized potassium permanganate solution was titrated thrice to give clear Mn2+ with an analyte of acidified FeSO4 until all the Fe2+ in the solution was oxidized to Fe3+. The color of the MnO4-/Mn2+ was used as the indicator for the titration. A balanced oxidation-reduction, the molarity/normality of the standards potassium permanganate, and the volume of potassium permanganate used allowed the determination of the concentration of the FeSO4.
Equipment and Chemicals:
Chemicals:
* Iron (II) ammonium sulfate solution, Fe(NH4)2∙6H2O, 0.100 M, 50 mL
* Manganese sulfate solution, MnSO4∙ H2O, 1.0 M, 50 mL
* Oxalic acid solution, H2C2O4, 0.25 M, 60 mL
* Potassium permanganate solution, KMnO4, approx. 0.02 M, 100 mL
* Sulfuric acid solution, H2SO4, 6 M, 50 mL
Materials:
* Buret, 50-mL
* Erlenmeyer flasks, 250-mL, 3
* Hot plate
* Thermometer
* Volumetric pipet, 10-mL
* Volumetric pipet, 25-mL
*