1835.] Chemical Analysis of Gadolinite, Sfc. 413 



These experiments seem to prove that the neutral oxalate 

 is a compound of, 



1 atom yttria . . . 5*5 



1 atom oxalic acid . 4*5 



2 atoms water . . . 2*25 



12-25 



Sesqui-oxalate of yttria. — When, instead of precipitating 

 the sulphate of yttria by the oxalate of ammonia, we reverse 

 the process, the precipitate is a sesqui-oxalate, as the follow- 

 ing experiments shew : — 



1st. 8*875 grs. of oxalate of ammonia were dissolved in 

 water, and a solution o ( f sulphate of yttria was added as 

 long as it occasioned a precipitate. The precipitate being 

 collected on a filter, and well washed and dried, weighed 

 9*43 grs. and after ignition 4*008 grs. of yttria remained. 



2nd. The same experiment being repeated, gave 9*9 grs. 

 of oxalate, leaving, after ignition, 4*092 grs. of yttria. 



Now, since 8*875 grs. of oxalate of ammonia contain 4*5 

 grs. of oxalic acid, we have from 



1st. experiment: 2nd experiment : 



Yttria . 4*008 or 5*5 - 4*092 or 5*5 

 Acid .4*5 „ 6* - 4*5 „ 6* 



This is nearly \\ atom acid to 1 atom base. 



Dinoxalate of yttria. — When yttria is precipitated from 

 a solution containing an excess of acid, by oxalic acid, we 

 sometimes obtain the neutral oxalate, but occasionally 

 another compound, which, however, has exactly the same 

 appearance. 



12*55 grs. of this, on ignition, left 9*45 grs. of yttria. 

 Hence, it seems to have been composed of, 

 2 atoms yttria . . 1*1 

 1 atom acid . . . 4*5 



Water 0*28 



Doubtless hygrometrical. 



4. Nitrate of yttria. — When nitric acid is poured upon 

 yttria, no immediate action takes place ; but, if the mixture 

 be gently heated the yttria dissolves at once, with the 

 evolution of nitrous gas. When evaporated the salt cry- 

 stallizes in prisms. When gently heated it melts into a 

 beautiful transparent glass, and is completely decomposed 

 by a very slight heat. It is very deliquescent. 



