A 2.00 mL sample of commercial bleach was diluted with water to a 100.00 mL volumetric flask. A 20.00 mL aliquot of the diluted sample was treated with excess KI. The liberated iodine was titrated with 0.1050 M Na2S2O3, requiring 12.5 mL to reach the starch indicator end point. Calculate the % w/v NaOCl in the sample.

A 2.00 mL sample of commercial bleach was diluted with water to a 100.00 mL volumetric flask. A 20.00 mL aliquot of the diluted sample was treated with excess KI. The liberated iodine was titrated with 0.1050 M Na2S2O3, requiring 12.5 mL to reach the starch indicator end point. Calculate the % w/v NaOCl in 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

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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