OF PALLADIUM AND PLATINUM. 
297 
should then become N 0 5 + Pd O . N H 3 , and correspond to the yellow crystalline form 
of the ammonia-chloride Pd . Cl + N H 3 , or the yellow ammonia-sulphate, S 0 3 . Pd O 
+ N H 3 . Adopting - this formula, the composition of the salt should have been 
One atom palladium . 
. 53*3 
40*29 
Two atoms nitrogen . 
. 28*0 
21*16 
Three atoms hydrogen 
. 3*0 
2*2 7 
Six atoms oxygen . . 
. 48*0 
36*28 
132*3 
100*00 
And with this the hydrogen and nitrogen determinations might be considered as per- 
fectly agreeing. However, from the irregular way in which this salt is decomposed 
I attach little value to the nitrogen result, and, on the other hand, the quantity of pal- 
ladium found exceeds that given by the formula as last written, too much to be ac- 
counted for by any error of experiment, as the crystals analysed were very pure. I 
hence consider that although the formula N 0 5 + Pd O . N H 3 agrees best with our 
received ideas, and with the analogies of other compounds, yet the former, N 0 5 
+ Pd . N H 2 , is more strictly deducible from the analytical results, and deserves at 
least provisional adoption until an opportunity presents itself of obtaining more de- 
cisive results, for I have found that this substance is not formed in all cases when 
its elements are brought together. I have procured it crystallized and sufficiently pure 
for analysis but twice, and then only in such small quantity as limited my power of 
experiment, as has been already seen. 
Double Oxalate of Palladium and Ammonia. 
This salt, which may be formed by adding oxalic acid to a solution of any colour- 
less ammonia-salt of palladium, or by dissolving the freshly-precipitated hydrated 
oxide, or basic carbonate in a solution of binoxalate of ammonium, crystallizes in 
very beautiful bronze-yellow rhombic prisms, which are of two kinds, differing in the 
quantity of water of crystallization which they contain. I shall describe them as 
being, the one form in short prisms, the other in needles. 
The short prismatic salt gave on analysis the following results : — 
31*225 grains gave, when very gently heated until the evolution of watery vapour 
ceased, 27'624 of dry salt, being 88*43 per cent. 
This dry substance being then ignited there remained 9*429 grains of metallic 
palladium, or 30*20 per cent. 
A quantity of the salt having been mixed with oxide of copper and introduced into 
a tube of German glass, with clean metallic copper in front, it was burned as for 
an organic analysis, and the relative volumes of nitrogen and carbonic acid in the 
gaseous mixture, which came over, were determined in the usual way. This relation 
varied very much in the different tubes full of gas, showing that the constituents of 
2 Q 
MDCCCXLII. 
