382 SIR WILLIAM CROOKES ON SCANDIUM. 



SCANDIUM PHTHALATE, 



When a solution of scandium nitrate is added to a solution of ammonium phthalate, 

 an amorphous white precipitate of scandium phthalate comes down. It is slightly 

 soluble in excess of scandium nitrate, and insoluble in water or in excess of ammonium 

 phthalate. Washed and dried in the air it contains one molecule of water and has 

 the composition given above; and after being heated for thirty-six hours to 110 it 

 loses half a molecule of water. Probably a little increase of temperature would have 

 rendered the salt anhydrous. I did not pursue the analysis further. 



A nalysis. 



fr251 gr. of air-dried scandium phthalate lost, on drying for thirty-six hours at 

 1 10, 0-192 gr. of water and left on ignition L'487 gr. of scandia, = 0'9629 gr- 



ot' scandium. 



Theory. Experiment. 



Sc 44-10 18-14 18-34 



8 H 5 O 6 . 181-04 



78-16 78-00 



9-01 



!)()! 370 3-66 



243-16 100-00 100-00 



The scandia resulting from the above analyses was dissolved in nitric acid and a 

 photograph taken of its spark spectrum. It was seen to be absolutely pure, with no 

 trace of lines belonging to other earths. The scandia remaining in the filtrate after 

 precipitating the phthalate was examined in the same way, and in its photographed 

 spectrum the dominant lines of yttrium and ytterbium could easily be detected, 

 accompanying the strong scandium spectrum. Experiments are now in progress to 

 find if a satisfactory method of separating scandium from yttrium and ytterbium can 

 be based on this reaction. 



SCANDIUM TETRACHLOROPHTHALATE, 



On mixing together equivalent proportions of scandium nitrate and ammonium 

 tetrachlorophthalate a dense white amorphous precipitate comes down, almost 

 insoluble in hot or cold water. When washed and dried in the air scandium 

 tetrachlorophthalate has the composition given above. 



