184 Moody — Iodometric Determination of Aluminium. 



determinations and the theoretical amount of alumina in neu- 

 tral aluminium chloride, sulphate, or alum, little time being 

 necessary for a single determination : 



n 



Measure 25 cm3 of the approximately — solution of the neu- 

 tral aluminium salt to be analyzed into a Yoit flask and to this 

 add a mixture of 10 cm3 of a solution of neutral potassium iodate 

 (30 grins, to a liter) and 1*0 grm. potassium iodide. Pass a cur- 

 rent of hydrogen through the liquid and heat for fifteen to 

 twenty-five minutes, or until the solution is nearly colorless, 

 collecting the iodine liberated in a Drexel flask, about half full 

 of water, in which 3 grms. of potassium iodide is dissolved. 

 Titrate with sodium thiosulphate the iodine in the Drexel 

 flask and that which remains in the solution in the Yoit flask, 

 and calculate the amount of alumina, A1 2 3 , corresponding to 

 the iodine, 61, liberated. 



The writer washes to thank Professor F. A. Gooch for 

 friendly assistance during this investigation. 



