SIR WILLIAM CROOKES ON SCANDIUM. 381 



The scandia used in the preparation of this salt was derived from the quantitative 

 analyses of other organic salts of scandium. Spectrum photographs showed that both 

 the scandia from the precipitated orthochlorobenzoate and that from the mother- 

 liquors were quite free from yttria and ytterbia. 



SCANDIUM METANITROBENZOATE, 

 [C 6 H 4 (NO 2 )COO] 3 Sc + 4H 2 O. 



Metanitrobenzoic acid is neutralised with ammonia, a hot solution of scandium 

 nitrate added till no more precipitate is formed, and the whole boiled for a few 

 minutes. A white crystalline precipitate falls down. The metanitrobenzoate is very 

 slightly soluble in water, and from a hot solution it separates in the form of flat 

 crystals displaying brilliant colours when examined by polarised light. The salt is 

 well washed, drained on blotting-paper, and dried over sulphuric acid in a desiccator. 



Analysis. 



(1) 5'624 gr. of scandium metanitrobenzoate left on ignition 0'607 gr. of scandia, 



= 0'3931 gr. of scandium. 



(2) 5"027 gr. of scandium metanitrobenzoate left on ignition 0'543 gr. of scandia, 



= 0'3516 gr. of scandium. 



(3) 7 '369 gr. of scandium metanitrobenzoate, dried at 1 10, lost 0'864 gr. of water, 



and left on ignition 0"800 gr. of scandia, = 0'5181 gr. of scandium. 



Theory. Experiment. 



(1). (2). (3). 



Sc ...... 44-10 7-18 G-99 7'00 7'03 



4H 2 O ..... 72-06 11-73 J |_1172 



614-29 100-00 100-00 lOO'OO lOO'OO 



The scandia used in these experiments was intentionally not quite pure, being 

 vitiated with a little yttria and ytterbia. On testing, the scandia resulting from the 

 decomposition of the metanitrobenzoate showed no trace of the dominant lines of 

 yttrium or ytterbium, while the earth precipitated from the mother-liquors of the 

 scandium metanitrobenzoate on spectroscopic examination showed strong lines of both 

 impurities. It will be remembered that NEISH found that metanitrobenzoic acid was 

 capable of separating thoria from its accompanying earths with quantitative accuracy. 

 Further experiments with this acid are in progress. 



