14 Preparation of Substances 



Enter the results as given below and have 

 them verified by an instructor. 



Amount of actual acid in 15 cc. of chamber acid, . .grams. 



Amount of ammonia equivalent to the acid, grams. 



Volum of gas hquor to contain the ammonia, cc. 



Procedure — Arrange a distilling appa- 

 ratus consisting of a flask of a capacity of 

 from 500 to 1000 cc. carrying a two-hole rub- 

 ber stopper. Thru one hole put a thistle 

 tube reaching to within 1 cm. of the bottom 

 of the flask, thru the other hole insert a 

 bent tube carrying a one-hole stopper fitted 

 to a condenser. Put 15 cc. of chamber sul- 

 furic acid into a 250-cc. gas bottle and adjust 

 to the delivery tube of the condenser so that 

 the bottle rests on the desk and the delivery 

 tube dips under the acid. Draw from 10 

 to 50 cc. more than the calculated amount 

 of gas liquor, — the amount depending 

 on its strength, — pour it thru the thistle 

 tube into the flask and begin heating. As 

 soon as the distillation is well under way, 

 look for the deposit of ammonium carbonate 

 in the condenser. If any appears — as it 

 always does — it will be necessary to break 

 up this compound in the flask by adding lime. 

 To do this make a paste of 10 to 15 grams of 

 lime and 50 to 75 cc. of water and pour 

 the mixture, which is milk of lime, thru a 



