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A chemistry student needs to determine the percentage of iron (Fe) present in a given iron ore sample using gravimetric analysis. The student is provided with the mass of the iron ore sample and a standardized solution of potassium dichromate (K2Cr2O7) to use for the analysis. What is the percent

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To determine the percentage of iron  Fe  in the given iron ore sample using gravimetric analysis, the student needs to follow these steps:1. First, the student needs to prepare the iron ore sample by dissolving it in an appropriate solvent, such as hydrochloric acid  HCl , to convert all iron into iron II  ions  Fe .2. The student then needs to titrate the iron II  ions in the solution with the standardized potassium dichromate  KCrO  solution. During the titration, the potassium dichromate oxidizes the iron II  ions to iron III  ions  Fe , while the dichromate ions  CrO  are reduced to chromium III  ions  Cr . The balanced chemical equation for this reaction is:6 Fe + CrO + 14 H  6 Fe + 2 Cr + 7 HO3. The student needs to carefully record the volume of the potassium dichromate solution used to reach the endpoint of the titration. The endpoint can be detected using an appropriate indicator, such as diphenylamine sulfonate, which changes color when all iron II  ions have been oxidized.4. Using the volume of potassium dichromate solution and its concentration, the student can calculate the moles of dichromate ions  CrO  used in the titration. From the balanced chemical equation, we know that 1 mole of dichromate ions reacts with 6 moles of iron II  ions. Therefore, the student can calculate the moles of iron II  ions in the iron ore sample.5. Knowing the moles of iron II  ions, the student can calculate the mass of iron  Fe  in the sample using the molar mass of iron  55.85 g/mol .6. Finally, the student can calculate the percentage of iron  Fe  in the iron ore sample by dividing the mass of iron by the mass of the iron ore sample and multiplying by 100.Please provide the mass of the iron ore sample and the concentration and volume of the potassium dichromate solution used in the titration to calculate the percentage of iron  Fe  in the sample.

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