440 F. H. Storer—Ammonia a contaminant of Sulphuric Acid. 
and I find, in fact, by direct experiment, that ammonia is 
formed when warm dilute nitric acid is made to act upon lead 
or upon sulphur. 
Action of dilute Nitric Acid on Lead—A quantity of soft, 
clean commercial lead that had just been remelted was placed 
in a small glass flask and 50 c. ¢. of dilute nitric acid (sp. gr. 
1°15) were poured upon it. The flask was closed against the 
air with a gas delivery tube, and after the action of the acid had 
ceased the solution was boiled with the milk of lime and the 
distillate tested for ammonia. But the reaction with Nessler'’s 
liquor was so strong that no estimation of the amount of 
ammonia could be made. A quantity of the lead (30 grams) 
boiled by itself in the milk of lime gave a distillate in which 
no ammonia could be detected by the Nessler test. On the 
other hand, 50 c. c. of the dilute nitric acid were found to con- 
tain 0000025 gram of ammonia. 
In a second trial 50 grams of the commercial lead were 
warmed during three hours with 50 c. c. of the dilute nitric 
acid. The solution was distilled with the milk of lime and the 
ammonia in the distillate was estimated by titration with 
standard oxalic acid :—0°002483 gram of ammonia was found. 
In a third trial 25 grams of pure lead (from Marquart of 
Bonn,) were warmed with 50. c. of the dilute nitric acid an 
acon gram of ammonia was found in the solution of nitrate 
of lead. 
distilled with milk of lime, and the ammonia estimated by 
Nessler’s test. 0°00004 gram of ammonia was found. 
Action of dilute Nitric Acid on Sulphur.—20 grams of pow- 
dered brimstone were added to 50 ¢. c. of the dilute nitric acid 
and the mixture was maintained at or near the temperature of 
boiling for three hours. On testing the liquid an abundance of 
ammonia was found. . 
In another trial, 20 grams of the powdered brimstone were 
mixed with 100 ¢. c. of the dilute nitric acid. The mixture 
was allowed to stand in the cold for 48 hours, and then boiled 
gently during 8 hours. On testing the liquor by the Nessler 
process 000225 gram of ammonia was found in it. 
_ A small amount of nitrogen oxides may perhaps be reduced 
to ammonia in the process of sulphuric acid making by oy 
deoxidizing agents, such as the organic impurities of crt 
sulphur,* or sulphuretted hydrogen,+ or even by sulphur 
acid, though in a single experiment in which sulphurous act®; 
* See Wagner’s Jahresberizht Chem. Technologi 149, 
+ Compare Johnston, in melin’s Handbook, i 296. 
