A 100.0-mL sample of spring water was treated to convert any iron present to Fe2+. Addition of 25.00-mL of 0.00250 M K2Cr2O7 resulted in the reaction 6Fe2+ + Cr2O7 2- + 14H+ → 6Fe3+ + 2Cr3+ + 7H2O The excess K2Cr2O7 was back-titrated with 9.40 mL of 0.00951 M Fe2+ solution. Calculate the concentration of iron in the sample in parts per million.

A 100.0-mL sample of spring water was treated to convert any iron present to Fe2+. Addition of 25.00-mL of 0.00250 M K2Cr2O7 resulted in the reaction 6Fe2+ + Cr2O7 2- + 14H+ → 6Fe3+ + 2Cr3+ + 7H2O The excess K2Cr2O7 was back-titrated with 9.40 mL of 0.00951 M Fe2+ solution. Calculate the concentration of iron in the sample in parts per million.

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

Chapter4: Stoichiometry: Quantitative Information About Chemical Reactions

Section4.9: Spectrophotometry

Problem 2.1ACP: Excess KI is added to a 100.0-mL sample of a soft drink that had been contaminated with bleach,...

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