Potassium dichromate is used to titrate a sample containing an unknown percentage of iron (AW. 55.845 g/mol ). The sample is dissolved in H3PO4/H2SO4 mixture reduce all of the iron to Fe<* ions. The solution is then titrated with 0.01625 M K2Cr207, producing Fe* and Cr* ions in acidic solution. The titration requires 32.26 mL of K2Cr207 for 1.2765 g of the sample.

Potassium dichromate is used to titrate a sample containing an unknown percentage of iron (AW. 55.845 g/mol ). The sample is dissolved in H3PO4/H2SO4 mixture reduce all of the iron to Fe<* ions. The solution is then titrated with 0.01625 M K2Cr207, producing Fe* and Cr* ions in acidic solution. The titration requires 32.26 mL of K2Cr207 for 1.2765 g of the sample.

Chemistry & Chemical Reactivity

10th Edition

ISBN:9781337399074

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter22: The Chemistry Of The Transistion Elements

Section22.7: Colors Of Coordination Compounds

Problem 3.3ACP

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