title: Properties of 4-amino-4'-methyldiphenylamine as a redox indicator.
abstract: The properties of 4-amino-4'-methyldiphenylamine as a redox indicator have been studied. The compound acts as a reversible, one-colour indicator, the oxidized form being red-violet, with molar absorptivity 6 x 10(3) l.mole(-1).cm(-1) at lambda(max) = 510 nm. The formal potential is described by the equation E = 0.735-0.059 pH. The two dissociation constants are pK(1) = -0.08 +/- 0.09 and pK(2) = 5.09 +/- 0.02. The relative error of titration of iron(II) with vanadium(V) is not larger than 0.2%.
authors.affiliation: Institute of Fundamental Problems in Chemistry, University, Warsaw, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Hulanicki
authors.forename: S
authors.initials: S
authors.lastname: Głab