418 



Gooch and Havens — Sejparation of 



rience) with some alkaline chloride, was dissolved in water and 

 converted bj ammonia to the form of the hydroxide, which was 

 thoroughly washed and dissolved in hot hydrochloric acid of 

 half-strength. From this solution, after cooling, gaseous hydro- 

 chloric acid precipitated the hydrous chloride in pure condi- 

 tion. The chloride thus prepared was dissolved in water and 

 the strength of the solution was determined by precipitating 

 the hydroxide from definite portions, and weighing the ignited 

 oxide in the usual manner. 



Table I. 



AI2O3 taken in 



solution as the 



chloride, 



grm. 



0-0761 



o-ovei 



00761 

 0-0761 

 0-0761 

 0-0157 

 00157 

 0-0157 

 0-0480 

 0-0960 



Al2v33 



Final 





found. ■ 



volume. 



Error. 



grm. 



em3 



grm. 



0-0746 



50 



0-0015 — 



0-0745 



50 



00016- 



0-0741 



50 



0-0020- 



0-0734 



50 



0-0027 — 



00756 



50 



0-0005 — 



0-0149 



45 



0-0008- 



0-0147 



40 



0-0010- 



0-0144 



45 



0-0013- 



0-0481 



30 



0-0001 + 



0-0957 



30 



0-0003- 



(1) 



(2) 

 (3) 

 0) 

 (5) 

 (6) 

 (1) 

 (8) 



(9) 

 (10) 



In the experiments recorded in "Table I, measured portions 

 of the standardized solution were submitted to the treatment 

 with hydrochloric acid and ether. The essential thing in the 

 process is to have at the end a mixture of the strongest aqueous 

 hydrochloric acid with an equal volume of anhydrous ether 

 saturated at a temperature of about 15° C. The most con- 

 venient way to secure these conditions seems to be to mix the 

 aqueous solution of the aluminum salt with a suitable volume of 

 the strongest aqueous hydrochloric acid — enough to make the 

 entire volume something between 15 and 25 cm^ — to saturate 

 this mixture with gaseous hydrochloric acid while the liquid is 

 kept cool by immersing the receptacle containing it in a cur- 

 rent of running water, to intermix a volume of ether equal to 

 the volume of the liquid, and finally, to treat the ethereal mix- 

 ture once more with the gaseous acid to insure saturation. 

 The precipitated crystalline chloride was collected upon asbestos 

 in a perforated crucible, washed with a previously prepared 

 mixture of hydrochloric acid and ether carefully saturated with 

 the gaseous acid at 15° C, and either ignited after careful 

 drying at 150° or redissolved in water, converted to the 

 hydroxide by ammonia in the usual way and weighed as the 

 oxide after filtration, washing, and ignition. In experiments 

 (1) to (4) the precipitated chloride was ignited directly ; in 



