title: Arsenazo III and its analogues-VII Colour reactions of the rare earth elements with a new reagent-carboxynitrazo.
abstract: A new reagent, Carboxynitrazo, gives a colour reaction with some rare earth elements. For the individual rare earth elements the sensitivities of the reactions are very different. The difference is greatest for the elements of the Ce- and Y-subgroups. For the first subgroup the molar absorptivities are about 16 x 10(4) l.mole(-1) cm(-1), whereas most of the elements of the Y-group do not give any colour reaction. A possible procedure for the determination of lanthanum in the presence of ytterbium is discussed.
authors.affiliation: V. I. Vernadsky Institute of Geochemistry and Analytical Chemistry U.S.S.R. Academy of Sciences MoscowRussia.
authors.forename: S B
authors.initials: SB
authors.lastname: Savvin
authors.forename: T V
authors.initials: TV
authors.lastname: Petrova
authors.forename: P N
authors.initials: PN
authors.lastname: Romanov