You are given a 200-mL sample of surface water from Lake Ontario, and asked to determine the chemical oxygen demand (COD) of the sample. To do so, you reflux the sample with 15 mL of a 0.2M K,Cr,O, standard solution for 2 hours, then titrate the excess dichromate using 20.0 mL of a 0.3M Fe2 solution. What was the COD of the sample (reported in mol/L of O2)? Reminder: Cr 0,2 consumes 6e", Fe2 offers le". A. The COD of the sample is O.010 mol/L O2 B. The COD of the sample is 0.008 mol/L O2 O C The COD of the sample is 0.015 mol/L O2 O D. The COD of the sample is 0.005 mol/L O2

You are given a 200-mL sample of surface water from Lake Ontario, and asked to determine the chemical oxygen demand (COD) of the sample. To do so, you reflux the sample with 15 mL of a 0.2M K,Cr,O, standard solution for 2 hours, then titrate the excess dichromate using 20.0 mL of a 0.3M Fe2 solution. What was the COD of the sample (reported in mol/L of O2)? Reminder: Cr 0,2 consumes 6e", Fe2 offers le". A. The COD of the sample is O.010 mol/L O2 B. The COD of the sample is 0.008 mol/L O2 O C The COD of the sample is 0.015 mol/L O2 O D. The COD of the sample is 0.005 mol/L O2

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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