Titer determination of KMnO4 by Potentiometric Titration
Use of ammonium iron sulfate as primary standard
Potassium permanganate is used to quantitatively determine the total oxidisable organic material in an aqueous sample. For the standardization of KMnO4 solutions,ammonium iron sulfate hexahydrate, (NH4)2Fe(SO4)2·6H2O (Mohr's salt) is used as an standard as it does not require heating while performing potentiometric titration.
Reaction:
MnO4- + 5 Fe2+ + 8 H+ --> Mn2+ + 5 Fe3+ + 4 H2O
This application determines the titer of aqueous 1/5 KMnO4 0.1 mol/L (0.02 mol/L KMnO4) titrant using ammonium iron sulfate as primary standard.
