104 HEINRICH ROSE ON THE COMBINATIONS OF 



acid. The anhydrous carbonate of ammonia is therefore differ- 

 ently circumstanced in this respect from the anhydi'ous sulphate 

 of ammonia, the constituent parts of which cannot be separated 

 by the same re-agents as those producing this effect with the 

 corresponding hydrous salts. Neither does the anhydi'ous car- 

 bonate of ammonia in solution differ in its action with all the other 

 re-agents from the other salts of the carbonate of ammonia, only 

 that (which arises from its composition) the carbonic acid of the 

 anhydi'ous neutral salt is entirely precipitated by solutions of the 

 chloride of barium, and of the chloride of calcium, whilst this takes 

 place in the solution of the other known combinations of carbonic 

 acid and ammonia only after the addition of ammonia. 



The anhydrous carbonate of ammonia is very easily soluble in 

 water. In the solid state it smells like free ammonia. This is 

 peculiar to all the combinations of carbonic acid with ammonia ; 

 but the greater the quantity of carbonic acid they contain, the 

 weaker is the ammoniacal odour. It is not perceptible at first 

 in the recently prepared combinations with excess of carbonic 

 acid, and not till they have been preserved in a vessel for some 

 time unexposed to the air. In the combinations, with more car- 

 bonic acid than contained in the neutral salt, this peculiarity 

 may be ascribed to the circumstance that they do not volatilize 

 undecomposed ; in the anhydrous neutral salt, however, this is 

 not the case, for it may be sublimed without changing its com- 

 position. 



The neutral carbonate of ammonia is exceedingly volatile, and 

 probably the most so of all the combinations of ammonia with 

 carbonic acid. If exposed to the air, it disappears entirely in 

 a short time. When sublimed, a very powerful ammoniacal 

 odour is diffused, which, liowever, entirely arises from the volatiU- 

 zation of the undecomposed salt. 0*569 grm. of the sublimed 

 salt, treated with chloride of platina, gave, after heating the pla- 

 tina salt obtained, 1"465G grm. of metallic platina. 0*930 grm. of 

 a second quantity of the sublimed salt gave, with a solution of 

 chloride of barium, 2*267 gvm. carbonate of barytes. Ammonia 

 still produced a sUght precipitate of 0*046 grm. carbonate of baiytes 

 in the filtered hquid, corresponding to 1*11 per cent, of carbonic 

 acid. The quantity of the platina answers to 44*79 per cent, of 

 ammonia, and that of the carbonate of barytes to 54*64, or, rather, 

 55*75 per cent, of carbonic acid, whence it evidently results that 

 the salt had undergone no change from sublimation. 



