SIE WILLIAM CKOOKES ON SCANDIUM. 375 



Analysis. 



(1) 6 - 254 gr. of scandium fumarate, heated to redness hi the air, left 2'287 gr. of 



scandia, = T4810 gr. of scandium. 



(2) 8'245 gr. of scandium fumarate left on ignition 3'055 gr. of scandia, = 1'9783 gr. 



of scandium. 



Theory. Experiment. 



(1). (2). 



Sc 44-10 23-95 23'68 23'99 



<JHO,. . .-13P02 7( ,. 05 7( .. 32 7( .. 01 



irloO 9 01 



184-13 100-00 100-00 100*00 



The scandia obtained in these analyses was tested in the spectrograph, and a 

 minute trace of yttrium and ytterbium lines was just detectable. The earth from 

 the mother-liquor showed the yttrium lines faintly and ytterbium lines strongly. 

 Further experiments are in progress with fumaric acid as a separating agent. 

 METZGER found this acid very effectual in separating thoria from other monazite 

 earths ; the present experiments give hopes that it may be useful in separating 

 scandium from ytterbium. 



SCANDIUM TARTRATE, 



CH(OH)COO. 



I >Sc(OH), 



CH(OH)COO X 



Scandium hydroxide is added to a strong solution of tartaric acid with slight 

 warming until the greater part of the scandium hydroxide is dissolved ; care must 

 be taken to keep the base in slight excess. The turbid solution is filtered and boiled, 

 when a granular precipitate comes down. This precipitate is well washed with 

 boiling water and. dried in a desiccator over sulphuric acid. 



In this way scandium tartrate forms a white crystalline powder, insoluble in hot, 

 slightly soluble in cold water, and insoluble in alcohol. Dried in a desiccator it is 

 anhydrous. When heated it emits the empyreumatic odour peculiar to decomposing 

 tartrates and leaves a white residue of scandia. 



Analysis. 



(1) 12'149 gr. of scandium tartrate left on ignition 4 - 027 gr. of scandia, = 2*6078 gr. 



of scandium. 



(2) 3'900 gr. of scandium tartrate'left on ignition T267 gr. of scandia, = 0'8205 gr. 



of scandium. 



