200 Minnig — Separation and Estimation of Aluminium. 



was present in a mixture of 2 grm. of the hydrous chlorides. 

 ]No determinations of the iron in the filtrate were made when 

 the pure acetyl chloride was used. 









Table IV. 









Solution of 



AlCl 8 .6H a O 



taken 



A1 2 3 



by 



standard 



Fe 2 3 used, 



present 

 as chloride 



A1 2 3 

 found 



Error 

 A1 2 3 





cm 3 . 



grm. 



grm. 



grm. 



grm. 



1. 



15 



0*1661 



0-0373 



0-1662 



+ 0-0001 



2. 



15 



0-1661 



0-0746 



0-1666 



+ 0-0005 



3. 



15 



0-1661 



0-1492 



0-1661 



o-oooo 



4. 



30 



0*1854 



0-0746 



0-1852 



— 0-0002 



5. 



30 



0-1854 



0-1119 



0-1860 



+ 0-0006 



6. 



30 



0-1854 



0-1865 



0-1862 



+ 0-0008 



7. 



30 



0-1854 



0-1865 



0-1856 



+ 0-0002 



8. 



30 



0-1854 



0-3730 



0-1856 



+ 0-0002 



* 9. 



30 



0-1854 



0-2611 



0-1856 



+ 0-0002 



*10. 



30 



0-1854 



0-3730 



0-1839 



— 0-0015 



11. 



45 



0-2781 



0-0746 



0-2779 



— 0-0002 



12. 



45 



0-2781 



0-0746 



0-2787 



+ 0-0006 



* After decanting the acetone-acetyl chloride solution of iron through the 

 filter and washing the precipitate of the hydrous aluminium chloride with 

 the precipitating mixture to remove as much of the iron as possible, the 

 precipitate in the beaker was dissolved in the smallest possible' quantity 

 of water and reprecipitated by the acetone-acetyl chloride mixture. There 

 is great danger of mechanical loss due to the creeping tendency of the 

 ferric chloride in acetone-acetyl chloride solution and the separation is 

 sharp enough to obviate any necessity of the second precipitation to avoid 

 danger of inclusion of the iron. 



The precipitation of hydrous aluminium chloride by the use 

 of the acetone-acetyl chloride [4 : 1] mixture is very simple, 

 quick and accurate and affords an easy method for the exact 

 determination of aluminium associated with iron. 



In conclusion it remains to thank Professor Gooch for his 

 kind advice and suggestions throughout the course of the 

 work. 



