620 Foreign and Miscellaneous Intelligence. 



11. ON THE COMPOUNDS OF AMMONIA WITH ANHYDROUS SALTS. 

 (By H. Rose.) 



In order to combine ammonia with anhydrous salts, I have employed 

 the following method : A current of ammonia was passed through 

 caustic potash, and then over a certain quantity of the salt, until, on 

 repeatedly weighing the compound, no further increase of weight 

 could be observed in it. The salt itself was placed in an oval 

 bulb, connected at both sides with long tubes of small diameter, 

 from which the atmospheric air was carefully shut out. I must, 

 however, observe that the addition of weight in the compound was 

 always rather less than what it ought to have been, because, before 

 the experiment, the air in the bulb was atmospheric, and after it am- 

 monial. The experiments were all made at common temperatures, 

 and whenever any evolution of heat was observed, the current of am- 

 monia was diminished. In most cases ammonia was rapidly taken 

 up at the beginning of the experiment, but gradual absorption went 

 on for a long time, so that, in many instances, the experiment was 

 continued for two days. 



In most of the compounds which ammonia thus forms with anhy- 

 drous salts, it combines in a different ratio from what is observed in 

 its compound with hydrates ; and the following description of some 

 of these combinations will perhaps serve to point out the laws by 

 which their formation is governed. 



Ammonia and Sulphate of Manganese. The absorption of am- 

 monia is slow, and unattended by any evolution of heat ; the com- 

 pound forms a white powder, which, after some time, becomes brown- 

 ish. 0.51 parts of the salt take up 0.328 parts of ammonia, or 100 

 parts of salt absorb 43.68 of ammonia, which is equal to 1 atom 

 of the former, and 4 atoms of the latter. In the open air it emits 

 ammonia ; the solution in water deposits protoxide of manganese ; 

 on being strongly heated, the ammonia is driven away; the re- 

 mainder becomes white, and is perfectly soluble in water. 



Ammonia and Sulphate of Zinc. Ammonia is rapidly taken up 

 by this sulphate with considerable evolution of heat ; the compound 

 is a voluminous white powder, consisting of 100 parts of the sulphate 

 and 51.22 of ammonia ; 1 atom of the salt, and 5 atoms of ammonia, 

 would be equal to 100 parts of the former, and 53.3 F. of the lat- 

 ter. It is not completely soluble in water, and deposits oxide of 

 zinc. On being strongly heated, it boils and emits ammonia, and a 

 small quantity of sulphite of ammonia. 



Ammonia and anhydrous Sulphate of Copper. The absorption of 

 ammonia by this sulphate is very rapid, and attended with evolution 

 of heat : the salt increases in volume, and becomes of a blue colour ; 

 0.54 parts of salt absorb 0.292 parts of ammonia, or one hundred 

 parts of the former take up 53.97 of the latter, which would cor- 

 respond to 1 atom of the sulphate to 5 atoms of ammonia, or 100 

 parts of the former to 53.77 of the latter. It is completely soluble 



