84 



SUBSTANCES SOLUBLE IN WJTEB. 



apparatus recommended by Schulzpi (Fig. 3), a weighed quantity 

 of powdered aluminium added, and solution of caustic soda slowly 

 from the deficit in the amount of hydrogen yielded the 



run m : 



Fig. 3. 



riitric acid present may be calculated. The following are the 

 details of the operation : 



A measured quantity of solution of caustic soda is introduced 

 into the pear-shaped flask B. The end of the glass-rod c is 

 accurately ground into the delivery-tube of B, so that no soda 

 can escape into A until the rod c is raised. The tube G is 



1 Zeitachr. f. anal. Chem. ii. 379, and vi. 379., 



