■ Dr. Kane on the Compounds of Ammonia. 41 



VI. OF THE AMMONIA-OXIDE OF COPPER. 



I had examined very frequently, and under a great variety of circumstances, 

 the precipitates which are produced by the action of ammonia on solutions of the 

 sulphate, nitrate, and chloride of copper, in order to determine whether com- 

 pounds similar to those generated under like circumstances with solutions of the 

 quicksilver salts, could be produced. In all such cases, I found the precipitates 

 to be basic salts following certain laws of composition, and not containing 

 ammonia as an element. Indeed a similar result might have been anticipated 

 from what has been already shown in this paper ; namely, that the insoluble 

 ammonia-copper compounds are all decomposed by water, giving soluble ammonia 

 compounds and a basic salt destitute of ammonia in its composition. 



However, on one occasion, on treating a solution of chloride of copper with 

 ammonia, I obtained a precipitate of a remarkably fine blue colour, approximating 

 to that of the hydrated oxide, or of the refiner's verditer. In the one operation 

 I obtained a sufficient quantity of it for examination, and did not since study 

 the exact circumstances favourable to its production, the specimen I had pro- 

 cured being sufficient to supply my wants, but proceeded at once to determine its 

 properties and composition. 



This blue powder is not affected by repeated washings, to which I subjected 

 it, suspecting that its ammoniacal constituent might result from sal ammoniac 

 being attached. It may be heated to 300° F. without being changed, but above 

 that temperature it is rapidly decomposed with a hissing noise. It yields much 

 ammonia, azote, and a large quantity of water, and the residue is red coloured, 

 consisting of a mixture of sub-oxide of copper and of copper in the metallic state. 

 There is no sublimate of sal ammoniac. 



Dissolved in dilute nitric acid, this powder gives no precipitate with nitrate of 

 silver. Its elements are therefore ammonia, water, and oxide of copper. The 

 following quantitative analysis was made : 



A. 3.410 grammes were dissolved in muriatic acid, and the solution decom- 

 posed by sulphuretted hydrogen. The sulphuret of copper having been removed, 

 the liquor and washings were evaporated to perfect dryness in a water-bath, and 

 sal ammoniac, weighing 1.634, was obtained, corresponding to 15.70 per cent, of 

 ammonia. 



VOL. XIX. O 



