Thorium precipitated as the Oxalate. 239 



• 





Series I. 







Precipitation by Addition of Oxalic 



Acid to Thorium 



Nitrate. 



Th0 3 

 taken as 

 nitrate 

 grm. 



Th0 2 found 



in treatment 



of precipitate 



grrn. 



Th0 2 found 

 in treatment 

 of filtrate 

 grm. 

 j 



Error in 



treatment 



of precipitate 



grm. 



Error in 



treatment 



of filtrate 



grm. 





Precipitation in hot solution. 





00216 

 00430 

 01074 

 01721 



00213 

 00425 

 01043 

 01670 



0-0210 

 0-0418 

 0-1040 

 0-1669 



—00003 

 —00005 



—00031 

 —00051 



—0-0006 

 —0-0012 

 —00034 

 —0-0052 



B. 

 Precipitation in cold solution. 



00237 00235 00234 —00002 —0-0003 



00242 0-0241 0-0236 —00001 —00006 



0-0474 00471 00471 —00003 —00003 



00474 00467 0-0470 —00007 —0-0004 



the precipitated oxalate from the normal form amounting 

 to about 1%. 



In the experiments of Series II, the order of addition 

 was reversed and the thorium nitrate solution was added 

 gradually to the oxalic acid with the intent to keep the 

 latter reagent in excess during the precipitation. The 

 mean error of the results shown in the experiments of 

 section B in which the precipitation was made in cold 

 solution amounts to about 0-1% while that of the experi- 

 ments of section A, made in hot solution, is practically 

 negligible. 







Series II. 







Precipitation by Addition of Thorium Nitrate to Oxal 



ic Add. 



Th0 2 



ThOa found 



Th0 2 found 



Error in 



Error in 



taken as 



in treatment 



in treatment 



treatment of 



treatment of 



nitrate 



of precipitate 



of filtrate 



precipitate 



filtrate 



grm. 



grm. 



grm. 

 A. 



ipitation in hot 



grm. 



grm. 





Prec 



solution. 





00216 



0-0217 



00212 



+00001 



—00004 



00431 



00432 



0-0428 



+00001 



—00003 



00646 



0*0646 



0-0643 



0-0000 



—00003 



0-0860 



0-0861 



0-0858 



+0-0001 



—00002 



01075 



01074 



01075 



—0-0001 



00000 



