Chalcones as inorganic analytical reagents - Part III. Spectrophotometric study of the germanium complex with 2′, 3′, 4′-trihydroxy chalcone
1·0–6·0 p.p.m. of germanium could be estimated spectrophoto-metrically with 2′, 3′, 4′-trihydroxy chalcone as reagent at pH 5·8–6·0. The complex was shown to contain three gram-moles of the reagent to one gram-atom of germanium both by Job’s method of continuous variations and the slope ratio method of Harvey and Manning. The instability constant was determined by the method of Edmonds and Birnbaum and found to be 1·670×10−11 at 28° C. It is concluded that complex formation involved only the two ortho hydroxyls in each molecule of the reagent and the carbonyl group played no part.