An 8.75-g sample of iron ore (mixture) is transformed to a solution of iron(II) sulfate, and this...
Question:
An 8.75-g sample of iron ore (mixture) is transformed to a solution of iron(II) sulfate, and this solution is titrated with 0.150 M {eq}K_2Cr_2O_7 {/eq} potassium dichromate. If it requires 67.8 mL of potassium dichromate solution to titrate the iron(II) sulfate solution, what is the percentage of iron {eq}(Fe) {/eq} in the iron ore?
{eq}6FeSO_4(aq) + K_2Cr_2O_7(aq) + 7H_2SO_4(aq) \to 3Fe_2(SO_4)_3(aq) + Cr_2(SO_4)_3(aq) + 7H_2O(l) + K_2SO_4(aq) {/eq}
Redox Titration:
Redox titration is usually used in metal cations and some other chemical species that are oxidizable by strong oxidizing agents such as permanganate ion and thiosulfate ion. Here, samples are pretreated so as to free up the analyte from the matrix of the solute.
Answer and Explanation: 1
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Here, the first thing that will be obtained is the number of moles of iron(II) sulfate. The stoichiometric ratio between iron(II) sulfate and...
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Chapter 3 / Lesson 18Identify the concentration of a common household chemical, hydrogen peroxide. Using a known concentration of potassium permanganate, you'll be able to perform a titration experiment to discover the unknown concentration of hydrogen peroxide.
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