Über niobsäuren und wasserlösliche alkaliniobate—I lichtabsorptions- und diffusionsmessungen an alkaliniobatlösungen

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Abstract

U.V.-spectrophotometric studies with aqueous solutions of potassium and sodium niobates within the pH-region 5–14 results in an appearance of three different spectra; thus the existence of three individual types of polyniobate is probable. From diffusion measurements it is shown, that in strong alkaline solutions of potassium niobate (pH 11–14)anionic weights of nearly 1000 predominate, whereas in less alkaline solutions (pH < 9) a high polymer species with roughly a threefold weight exists.

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