DE. A. W. HOFMANN ON THE PHOSPHOEUS-BASES. 
623 
Theory, 
A 
Experiment. 
A 
( 
1 
( ' 
I. 
II. 
III.' 
I equiv. of Arsonium . . 
. 270-0 
56-82 
I equiv. of Platinum . . 
. 98-7 
20-77 
21-04 
20-90 
21-18 
3 equivs. of Chlorine 
. 106-5 
22-41 
I equiv. of Platinum-salt . 
. 475-2 
100-00 
Compounds of Vintl-triethylarsonium. 
The bromide of bromethyl-triethylarsonium, like the corresponding phosphorus-com- 
pound, loses its latent bromine under the influence of oxide of silver. If the solution 
of the bromide be precipitated by an excess of nitrate of silver, one-half of the bromine 
separates as bromide of silver ; the clear filtrate, mixed with ammonia, yields the second 
half of the bromine in the form of a dense precipitate. Nevertheless the reaction differs 
from that observed in the phosphorus-series. The bromide of the bromethylated phos- 
phonium, as has been pointed out in a former part of this inquiry, is almost invariably 
converted into an oxethylated body, its transformation into a vinyl-compound being 
altogether exceptional. The bromide of the bromethylated arsonium, on the other hand, 
fields, as a rule, the vinyl-body of the series, the formation of an oxethylated compound 
taking place only under particular circumstances; in fact so rarely as to leave some 
doubt regarding the existence of this term of the series. The bromide of the brom- 
ethylated arsonium, treated with an excess of oxide of silver, yields a powerfully alkaline 
solution, the nature of. which was determined by the analysis of the corresponding plati- 
num-salt. Transformed into the chloride, and precipitated with dichloride of platinum, 
this solution pelded beautiful rather soluble octohedra. 
I. 0'6312 grm. of platinum-salt, treated with sulphuretted hydrogen, &c., gave 0T570 
grm. of platinum. 
II. 0’6338 grm. of platinum-salt, analysed in the same manner, gave 0T57I grm. of 
platinum. 
III. 0-4345 grm. of platinum-salt gave 0-1093 grm. of platinum. 
IV. 0-4135 grm. of platinum-salt gave 0-1025 grm. of platinum and 0-4525 grm. of 
chloride of silver. 
V. 0-3370 grm. of platinum-salt gave 0-0843 grm. of platinum. 
These numbers lead to the percentages of a vinyl-triethylarsonium-compound. The 
formula 
C, H,8 As Pt Qj = [(C, Hj) (C^ H,)^ As] Cl, Ft Cl, 
requires the following values : — 
3 z 2 
