Beiträge zur Kenntniss der Absorptionsspectra erzeugenden seltenen Erden

Abstract

431. P a u l K i e s e w e t t e r und Gerhard Kruss: Beitrage zur Kenntniss der Absorptionsspectre erzeugenden seltenen Erden.[Mittheilung aus dem chemischen Laboratorium der konigl. Akademie der Wissenschaften zu Miinchen.] (Eingegangen am 22. Juni; mitgetheilt in der Sitzung van Hrn. A. Pinner.)Jenes Oxyd, welches noch vor ungefahr zebn Jahren als Erbinerde bezeichnet und als das Oxyd eiues einfachen Elementes betrachtet wurde, besteht wie bekannt nach den interessanten Untersuchungen von M a r i g n a c , S o r e t , N i l s o n , C l e v e , B r a u n e r und Anderen zum mindesten aus sieben verschiedenen Erden, aim der Scandin-, Ytterbin-, Thulin-, Erbin-, Terbinerde, aus derjenigen, welche S o r e t mit X benannte, und aus der Ittererde. Fernerhin zeigte vor wenigen Jahren L e c o q d e B o i s b a u d r a n durch fractionirte Fallung der S o r e t'schen Erde X und spectroskopische Untersuchung der einzelnen Fractionen, dass das X, oder C l e v e ' s Holmium, aus zum mindesten zwei Elementen besteht; zugleich ging ails den interessanten Ontersuchungen von W. C r o o k e s hervor, dass wir es in der Ittererde wohl nicht mit dem Oxyd nur eines Elernentes zu thun haben. So ist das

The Basicity Characteristics of Scandium, Yttrium, and the Rare Earth Elements.

“…As experimental evidence for the relatively high basicities of the oxides of these elements, one can cite the ease with which even the strongly ignited oxides of all but scandium dissolve in acids (66,79,250,263,285,305,416); dissolve in ammonium salt solutions with the liberation of ammonia (20,21,45,244,250,263,343); dissolve in aniline hydrochloride solutions (233); react with such hightemperature acids as ammonium salts (5,146,147,181,351,352,394,450), borax (31,154), metaphosphate (31), and alkali bisulfate (231,363) or pyrosulfate (11, 212); and absorb atmospheric carbon dioxide (114,250,263,278,285). To these can be added the comparatively high water solubilities and precipitation pH values of the hydrous oxides and hydroxides (64,65,74,167,222,297,327,361,389,398), the tendencies of at least some of the oxides to slake with water (244, 250, 278, 285), the absorption of carbon dioxide by hydrous lanthanum (12,...…”

“…Crookes(93) purified yttrium by nitrate fusion and used Debray's modified procedure to remove cerium (94) and to separate scandium from ytterbium (97). Prior to 1910, nitrate fusion was used by many other workers to fractionate the yttrium earths(22,23,40,81, 169,212,234,367,369) and the cerium earths(10,22,23,137,331,365,366,443,444). Bettendorff(22) obtained clear melts for the yttrium earths because the melting points lay below the decomposition temperatures but always noted decomposition of cerium earth nitrates before fusion.…”

Chemists and physicists behaving badly: The shadow side of two elemental discoveries

“…Six years later, Carl Auer von Welsbach (1858-1829) extracted two other elements from didymium: neo-didymium (neodymium) and praseo-didymium (praseodymium). In 1886, William Crookes (1832Crookes ( -1919 [2] stated that Nd and Pr were a mixture of several elements including element 61; Eugène-Anatole Demarçay (1852Demarçay ( -1903, Henri Becquerel (1852-1908, M. G. Tomson, and Ksewetter came to similar conclusions [3][4][5][6][7][8].…”