488 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 54 



YTTRIUM. 



Xearly all the rcg-ular detonniiialinDs of the atomic weight of yttrium 

 depend upon analyses or syntheses of the sulphate. A series of analyses 

 of the oxalate, however, by Berlin/ is sometimes cited, and the data are 

 as follows. In throe experiments upon the salt Yt2(Co04)3.3H„0 the 

 subjoined percentages of oxide wore found : 



45.70 

 45.65 



45.72 



Mean, 45.69, ± .0141 



Hence Yt = 89.55. 



The early work of Berzelius ' may be ignored. The first determinations 

 of the atomic weight of yttrium to be considered are those of Popp,^ who 

 evidently worked with material not wholly free from earths of higher 

 molecular weight than yttria. The yttrium sulphate was dehydrated at 

 200° ; the sulphuric acid was then estimated as barium sulphate, and 

 after the excess of barium in the filtrate had been removed the yttrium 

 was thrown down as oxalate and ignited to yield oxide. The following 

 are the weights given by Popp : 



Eliminating water, these figures give us for the percentages of YtoO,, in 

 Yt, (804)3 tiie values in column A. In column B I put tlio quantities of 

 Yt^Og proportional to 100 parts of BaSO^: 



A. B. 



51.237 36.075 



51.226 36.064 



51.161 36.058 



51.209 36.055 



Mean, 51.208, ± .011 Mean, 36.003, ± .003 



Hence Yt= 102.05 from A, 102.27 from B. 



1 Forhandlingar ved de Skandinaviske Naturiorskeies, 8, 452. .1860. 



- Lehrbuch, 5 Aufl., 3, 1225. 



" Ann. Chcm. Pharm., 131, 179. 1864. 



