title: Determination of potassium with alkali-heavy metal cobaltinitrites.
abstract: A procedure is proposed for the removal and determination of K(+) by precipitation with [Co(NO(2))(6)](3-) in the presence of Pb(2+) and H(2)O(2). The whole precipitate is dissolved, the Co(3+) estimated colorimetrically, and the K(+) content calculated, with a relative error of 1%. The potassium-containing precipitate may also be dissolved in NaOH + NH(3) solution, the Co(3+) titrated complexometrically, and the potassium content deduced. These two procedures may be modified for the removal and determination of Pb(2+), Co(2+), Co(3+) and NO(2)(-). Na(+) ions do not interfere.
authors.affiliation: Department of Inorganic and Analytical Chemistry The Hebrew University of Jerusalem Israel.
authors.forename: A H
authors.initials: AH
authors.lastname: Ben-Bassat