An iron ore sample is analyzed for iron content by dissolving it in acid, converting the iron to...
Question:
An iron ore sample is analyzed for iron content by dissolving it in acid, converting the iron to Fe+2 and then titrating with standard 0.0150M Kt2 Cr2 O7 solution. If 32.05 mL is required to titrate the iron in a 1.7221 gram ore sample, how much iron is in the sample, expressed percent Fe_20O_? Each Cr2 O7-2 reacts with 6 Fe+2 (=3 Fe2 O3). Note that in the experiment you will calculate the percent Fe3+, not Fe2 O3.
Stoichiometry
Knowing the molar ratios between the chemical species within a chemical reaction allows one to convert the amount of one chemical species to another in the reaction. It should be noted that the amount of the chemicals species must be in the unit of moles before the ratio can be applied.
Answer and Explanation: 1
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View this answerFe is 9.35% of the ore.
We are given that every mole of {eq}Cr_2O_7^{-2}{/eq} will react with 6 moles of {eq}Fe^{+2}{/eq}, so we can write two...
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