For the next 3 items: A 100.0-mL sample of spring water was treated to convert iron to Fe2 (55.85 g/mol) The addition of 25.00-mL of 0.001678 M K2Cr20, resulted in the following reaction: 6FE2* + Cr,0,2 + 14H* → 6FE3* +2Cr3+ + 7H20 The excess K,Cr20, was back titrated with 7.53 mL of 0.00959 M Fe2*. Calculate the number of moles of excess Cr:O;- that remained in the solution. 1.20 x10-5 mol 4.33 x10-4 mol O 0.012 mol 0.433 mol

For the next 3 items: A 100.0-mL sample of spring water was treated to convert iron to Fe2 (55.85 g/mol) The addition of 25.00-mL of 0.001678 M K2Cr20, resulted in the following reaction: 6FE2* + Cr,0,2 + 14H* → 6FE3* +2Cr3+ + 7H20 The excess K,Cr20, was back titrated with 7.53 mL of 0.00959 M Fe2*. Calculate the number of moles of excess Cr:O;- that remained in the solution. 1.20 x10-5 mol 4.33 x10-4 mol O 0.012 mol 0.433 mol

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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