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CH3041
TITRATIONS
Direct titration: a standard
titration where the titrant (burette) is added to the analyte(flask)
until the reaction is complete.
eg titrant
(KMnO4) + fulvic
acid® faint pink
• Example: hardness
Back titration: a known ‘in excess amount’ of standard reagent is
added to the analyte.
The excess that does not
react is accurately ascertained using the titrant solution.
• End points are sometimes easier to see.
eg react (x + y)KMnO4 + x fulvic acid
titrant (Fe2+) + excess yKMnO4 ® colourless
• Examples are: COD and ANC
