(a) Oxygen demand is an important parameter for assessing the extent of organic pollution in water. (i) (ii) Write a note on Oxygen Demand Testing. Describe the colorimetric laboratory test for Total Organic Carbon, including any relevant chemical reactions. In the laboratory, a 50 cm' water sample was analysed for Chemical Oxygen Demand (COD) through titration with NazCr2O, (0.002 M). Calculate the COD in mg/L O2, given that the titre was 20.80 cm. (iii)

(a) Oxygen demand is an important parameter for assessing the extent of organic pollution in water. (i) (ii) Write a note on Oxygen Demand Testing. Describe the colorimetric laboratory test for Total Organic Carbon, including any relevant chemical reactions. In the laboratory, a 50 cm' water sample was analysed for Chemical Oxygen Demand (COD) through titration with NazCr2O, (0.002 M). Calculate the COD in mg/L O2, given that the titre was 20.80 cm. (iii)

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter13: Titrations In Analytical Chemistry

Section: Chapter Questions

Problem 13.5QAP

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