YTTRIUM. 133 



YTTRIUM. 



The composition of yttrium oxide is not definitely settled. 

 Mendelejeft" concludes from the general behavior of its 

 compounds that it is a sesqui-oxide. As, however, all the 

 chemists who have made atomic weight determinations of 

 this element have considered it a prot-oxide, I shall assume 

 it to be so and the atomic weight, therefore, about 60. 



J. J. Berzelius : 6Jf..^9 (O = 16); 401.84 (O = 100). 



This determination was made before the discovery of 

 erbium and can scarcely be correct. The value was reached 

 by analysis of the sulphate with barium chloride. Ba = 

 856.88, 8 = 201.165. [Poggend, Ann., 8, 1826, 186; 10, 

 1827, 341.) 



X. J. Berlin: 59.7 (0 = 16). 



According to Blomstrand in Berlin, Ber. der Cheni. Ges., 

 1873, 1467. I can find no other record of this determina- 

 tion which probably appeared in the Forhandl. ved de Skandi- 

 naviske Naturforsk, 1860, 448. 



0. Popp : 68 (0 = 16), 



The mean of four analyses of the sulphate showed that 

 40.15 oxide were equivalent to 38.23 sulphuric anhydride, 

 giving a molecular weight for the oxide of 42.015 ; extreme 

 difierence, 0.013. The yttrium was precipitated with sub- 

 limed oxalic acid, the free acid being afterwards neutralized 

 with ammonia. The sulphuric acid was precipitated with 

 barium chloride in the filtrate with precautions. Popp, who 

 denies the existence of erbium and terbium, separated yttri- 

 um from the cerite oxides by precipitation with barium 

 carbonate, yttrium remaining in solution, S = 16, Ba = 

 68.5. {Liebifs Ann., 131, 1864, 183.) 



M. Delafontaine : about 64 (0 = 16). 



Delafontaine does not pretend that this number is exact. 

 It is derived from analyses of the sulphate. His method 

 of separation was essentially Mosander's, which was proved 

 by Popp and by Bunsen and Bahr to give impure salts. 

 {Lkbig's Ann., 13J^, 1865, 108.) 



