Change to read:
Oxidizable substances
To 100 mL, add 10 mL of 2 N sulfuric acid, and heat to boiling. Add
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0.2 mL
USP29 of
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0.1 N
USP29 potassium permanganate, and boil for 5 minutes. The pink color does not completely disappear; or alternatively follow the test method for
Total Organic Carbon
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.