OF PALLADIUM AND PLATINUM. 
291 
Of the Ammonia-sulphates of Palladium. 
On adding water of ammonia to a solution of sulphate of palladium, no ammonia- 
cal compound is at first obtained, but merely the basic compound already described. 
When, however, the ammonia is added in excess, the basic salt redissolves, and a 
colourless liquor is produced, from which the ammonia-sulphate may be obtained 
crystallized, by cautious evaporation and cooling. 
This salt is best obtained by taking a strong solution of the neutral sulphate, and 
passing into it a stream of ammoniacal gas until the brown precipitate which first 
appears is totally redissolved ; then filtering, if necessary, and setting aside to cool 
slowly. It then forms rectangular prisms, often of considerable size and of a beau- 
tiful pearly lustre. 
When this salt is very gently heated, it gives off water, and the crystals become 
opake, but without losing their form or whiteness. Ammonia is next evolved, and the 
salt changes into a yellow powder, which, when more strongly heated, fuses, evolves 
sulphite of ammonia, ammonia, nitrogen, and water, and leaves metallic palladium. 
A very finely crystallized specimen was analysed as follows : — 
A. 25*987 grains decomposed by very full ignition gave 9*414 grains of palladium, 
or 36*24 per cent. 
B. 48*677 grains dried at a very moderate heat as long as any water was evolved, 
but without any loss of ammonia, and remaining quite white, then weighed 45*672 
grains, having lost 6T9 per cent, of water. 
17'039 grains of this dry material gave by bright ignition 6*591 grains of palladium, 
which is 38*68 per cent, for the dry, and 36*28 for the hydrated salt. 
C. 28*462 grains of the crystals were fused with carbonate of soda and the mass 
treated with boiling water. The metallic palladium which remained weighed 10*340 
grains, or 36*50 per cent. 
The alkaline liquor acidulated by nitric acid and treated with nitrate of barytes, 
gave 22*827 grains of sulphate of barytes, indicating 2 7*67 per cent, of sulphuric acid. 
These results may be thus exhibited. 
Hydrated Salt. 
A. B. C. 
Dry Salt. 
Water . . . 
6*19 
Sulphuric acid . 
27-67 
29*49 
Palladium . . 
. 36*24 36*28 36*50 
38*68 
These results abundantly show that the formula of this salt is, when crystallized, 
S 0 3 + Pd O + 2 N H 3 -f- H O, which gives 
S O s = 40*1 27*75 
Pd = 53*3 36*95 
O = 8*0 5*54 
2 . N H 3 = 34*0 23*53 
H O = 9*0 6*23 
144*4 10000 
2 p 2 
