Germanomolybdic acid and its reaction with basic organic dyestuffs-I Spectrophotometric determination of ge(iv) with xanthene dyes.

The interaction between germanomolybdic acid and four xanthene dyes (Rhodamine B, Rhodamine 6G, Rhodamine S and Pyronine G) is studied and the conditions for spectrophotometric determination of Ge(IV) with these reagents are established.

Spectrophotometric determination of germaninm(IV) with bromopyrogallol red.

A method is proposed for the spectrophotometric determination of germanium with Bromopyrogallol Red. A red-violet coloured complex is formed at pH 2-3, with a stoichiometry equivalent to Ge(BPR)(2), and a molar absorptivity of 20.5 x 10(3) at 550 mmu. Beer's law is obeyed over the range 0.2-3 ppm. Germanium in cupriferous ores has been determined by the method.