The standardization of same titrant during the determination of BOD5 of water sample was done separately for Day 1 and Day 5. Upon standardization, it turned out that the concentration of the titrant in Day 1 is higher than the concentration of the same batch of titrant in Day 5. How would you explain this discrepancy? The water used to prepare the Na2S2O3 solution was not boiled resulting to proliferation of bacteria. Too much starch indicator was added in the conical flask. Sulfuric acid was added first before potassium iodide. There were bubbles at the tip of the burette during titration.

The BOD5 test, also known as the Biochemical Oxygen Demand test, is a biochemical test that measures…

The standardization of same titrant during the determination of BOD5 of water sample was done separately for Day 1 and Day 5. Upon standardization, it turned out that the concentration of the titrant in Day 1 is higher than the concentration of the same batch of titrant in Day 5. How would you explain this discrepancy?

The standardization of same titrant during the determination of BOD5 of water sample was done separately for Day 1 and Day 5. Upon standardization, it turned out that the concentration of the titrant in Day 1 is higher than the concentration of the same batch of titrant in Day 5. How would you explain this discrepancy?

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter3: Statistical Tests With Excel

Section: Chapter Questions

Problem 6P

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The standardization of same titrant during the determination of BOD5 of water sample was done separately for Day 1 and Day 5. Upon standardization, it turned out that the concentration of the titrant in Day 1 is higher than the concentration of the same batch of titrant in Day 5. How would you explain this discrepancy? (A) There were bubbles at the tip of the burette during titration. (B) Too much starch indicator was added in the conical flask. Sulfuric acid was added first before potassium iodide. (D) The water used to prepare the Na₂S₂O3 solution was not boiled resulting to proliferation of bacteria.
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