ge ee eS ee ee ee ee ee Oe ee ee 
et ee ee eee 
23. The Double Mercuri-periodides of Substituted Ammo- 
nium Bases. Tetrapropylammonium Mercuri-periodide. 
By Rasix Lat Datra and Haripas MUKHERJEA. 
In a paper to the Chemical Society (Trans. Chem. Soc., 
1913, 103, 426), it has been pointed out by one of us that when 
platinic chloride or cupric chloride is added to substituted 
the case of double platinic eh the platinic iodide itself is 
stable and no special care has to be taken for preparing the 
double salts, but in the case of oy salts with cupric iodide, 
the cupric iodide is unstable, decomposing into cuprous iodide 
and ee 
as been pointed out before that the heavily substituted 
eae bases form with remarkable facility the double 
tig’ iodides, since they contribute materially to their forma. 
tion by reason of the affinity of those bases for iodine. It is 
for this reason that no double salt of cupric iodide has been 
ress with the iodides of alkali metals and lightly substi- 
ted ammonium bases, while the platinic iodides form double 
iodides with them with great ease. 
There is, then, a strong affinity of the substituted ammo- 
This strong affinity of the bases for iodine suggested to us the 
area “of formation of double salts in which there are 
uigher valencies in existence as regards iodine and accordingly 
the pe gbgces of double Born gal ax oe was undertaken. 
n this case the method of preparation has been varied 
a little froin the usual method of double serge gaies a in as 
much as the hexavalent mercury atom has not been realized in 
the case of any salt of mercury. In the case of cloubie salts 
with cupric iodide, we had a parallel valency in cupric chloride 
and hence the method of double decomposition was feasible. 
The following direct method has been used successfully for the 
dissolved in a solution of potassium iodide. The resulting 
solution contains presumably Hgl, in a very loose "added of 
