Theory of Gunpoivder . 495 



the amount of hydrochloric acid equivalent to the carbonate of 

 ammonia sought, from which the carbonate of ammonia is ob- 

 tained from the equation 



_ 2(NH''0),3CO^ u{ty-t) 

 •^'~ 2HC1 • /i • 



The experiment gave for t and /, the same value, which proves 

 the entire absence of ammonia. 



7. Determination of Nitre. — The liquid containing 1 grm. 

 residue in which no ammonia was found, was feebly acidified 

 with pure sulphuric acid, and treated with pure sheet zinc of the 

 thickness of tinfoil. The liquid was kept in cold water, and sul- 

 phuric acid gradually added during several hours, so that the 

 zinc dissolved up with the feeblest evolution of gas. When the 

 solution of the zinc, and therewith the coiaversion of nitric acid 

 into ammonia, was complete, the liquid was mixed with more 

 potash than was necessary to redissolve the precipitated oxide of 

 zinc, and the ammonia formed determined in the manner just 

 described. 



Retaining the same meaning for the letters used in (6), we 

 have .r,, the quantity of nitrate sought, 

 KO,NO^ u 

 ^'~ HCl 'V^' ^^• 

 Experiment gave « =0-05612 grm., /,=27-0, /=180, from 

 which we get for x^ the value 005185 grm. 



8. Determination of Carbonate of Potash. — A measure of the 

 liquid containing 1 grm. residue, was precipitated by a solu- 

 tion of recently fused chloride of manganese ; the precipitate fil- 

 tered oS" was dried, and treated, together with the filter, with di- 

 lute sulphuric acid in a carbonic acid apparatus. The liquid was 

 rejjcatedly heated to expel the carbonic acid. The loss of weight 

 amounted to 00860 grm., which corresponds to 27'016 per cent, 

 carbonate of potash, or 2'34:52 charcoal, or 1 8*41 7 potash, or 

 39-525 nitre. 



9. Determinationof Hydrate of Potash. — The protoxide of man- 

 ganese dissolved in the carbonic acid apparatus in the last deter- 

 mination, gave when precipitated with carbonate of soda, 0'1654 

 grm. manganoso-manganic oxide. Now 3 atoms MnO, CO^, or 

 3 atoms CO^ correspond to 1 atom Mn^O". The 0086 grm. 

 carbonic acid found ia the carbonate of manganese corresponds 

 to 0-1495 Mn^O"; this 0*1495 grm. Mn3 0^ subtracted from 

 0"1654 grm., leaves 0'0159 grm. Mn'^O*, which therefore was 

 not present in the original precipitate as carbonate, but as hy- 

 drate of protoxide of manganese. Three atoms of I\InO are 

 equivalent to 1 atom Mn-'O', and require 3 atoms KO 110 for 

 their precipitation ; Mn^'O'' corrcsjjonds therefore to 3 atoms 



