Light Absorption Spectrometry

Abstract

The literature relevant to light absorption spectrometry for the period July 1957 to September 1959 has been sampled for this eighth in a series of reviews (422, 424)• In endeavoring to make a judicious selection of references primarily of interest to analytical chemists, mampapers of some relevance were omitted. The classification of subject matter again is chemistry, physics, and applications.Attention is directed to several publications devoted entirely, or in part, to spectrophotometric analysis. "Colorimetric Analysis" (12), "Colorimetric Determination of Non-Metals" (75), "Colorimetric Determination of Traces of Metals," third edition (574), and "Colorimetric Methods of Analysis," Volume IIA (628), are recent treatises. A "1959 Supplement to the Bibliography heteropoly formation was found only at pH 9 to 11 (640). Molybdosilicic acid with molybdenum-silicon ratios of 12:1, 6:1, and 2:1 has a yellow hue which increases with the number of molybdate groups present (551). The 1:1 heteropoly complex is colorless. A decrease in hue with time takes place at all pH values where the 12:1 complex exists, but this change is due to structural rearrangement rather than to decomposition. Molybdic acid forms 1:1, 1:2, and 2:1 complexes, respectively, with erythritol, mannitol, and gluconic acid. The erythritol and gluconic acid complexes exhibit most of the normal reactions of molybdates (545).