A typical sample of iron ore contains both Fe2+ and Fe3+ ions. The total amount of iron present in the ore can be determined by dissolving a sample of the ore in an acid solution, reducing all the iron present to Fe2+ and titrating the resulting solution with a standard potassium permanganate solution as follows: A 4.730 g sample of the ore is dissolved in hydrochloric acid and passed over a reducing agent to convert all the iron to Fe2+ This solution is quantitatively transferred to a 150.00 mL volumetric flask and made up to the mark. A 15.00 mL portion of this solution is pipetted into a conical flask, and titrated with a 0.0512 M KMnO4 solution. The endpoint of the titration is determined when the colourless solution in the conical flask turns a bright pink due to the presence of excess permanganate ions. The average titration value is 31.60 mL of the KMnO4 solution. The reaction stoichiometry is as follows: KMnO4(aq) + 8HCl(aq) + 5 FeCl2(aq) -> 2MnCl2(aq) + 4H2O (l) + 5 FeCl3 (aq) + KCl (aq) a. Determine the percentage of iron in the ore. b. Naturally occurring manganese consists of only the Mn 55Mn isotope. Determine the moles of the manganese salt formed, and then calculate the total number of neutrons present in all the manganese ions in the final solution.
A typical sample of iron ore contains both Fe2+ and Fe3+ ions. The total amount of iron present in the
ore can be determined by dissolving a sample of the ore in an acid solution, reducing all the iron present
to Fe2+ and titrating the resulting solution with a standard potassium permanganate solution as follows:
A 4.730 g sample of the ore is dissolved in hydrochloric acid and passed over a reducing agent to
convert all the iron to Fe2+
This solution is quantitatively transferred to a 150.00 mL volumetric flask and made up to the mark.
A 15.00 mL portion of this solution is pipetted into a conical flask, and titrated with a 0.0512 M KMnO4
solution.
The endpoint of the titration is determined when the colourless solution in the conical flask turns a
bright pink due to the presence of excess permanganate ions.
The average titration value is 31.60 mL of the KMnO4 solution.
The reaction stoichiometry is as follows:
KMnO4(aq) + 8HCl(aq) + 5 FeCl2(aq) -> 2MnCl2(aq) + 4H2O (l) + 5 FeCl3 (aq) + KCl (aq)
a. Determine the percentage of iron in the ore.
b. Naturally occurring manganese consists of only the Mn 55Mn isotope. Determine the moles of the manganese salt formed, and then calculate the total number of neutrons present in all the manganese
ions in the final solution.
Step by step
Solved in 3 steps
