x 
ie 
On the Ammonia-cobalt Bases. 319 
Art. XXXIII.— Researches on the Ammonia-cobalt Bases ; by 
Wotcorrt Gress and F. A. GENTH. Part L 
Continued from page 265. 
CHLORPLATINATE OF PURPUREOCOBALT. 
WHEN a solution of bichlorid of platinum is added to one of 
the chlorid of Purpureocobalt, a brown-red precipitate is thrown 
Own, which is a combination of the two chlorids. When dried 
it has a fine rich brown-red color and high lustre. The crystals 
Seen under the per: are usually aggregations of flat pale 
reddish-brown needles. They are very distinctly dichrous, the 
ordinary i image being ale violet-rose, while the parca 
Image A ie orang 
tution of these ceyEes, but acd ac are aot sivorplstinate of am- 
Monium. Sulphurous ‘acid reduces this double chlorid readil 
and yields a red solution containing the. Sperone of plati- 
hum and of cobalt. We may here r that so far as our 
observation has hitherto extended, the action of a reducing 
agent upon any constituent of a compound containing an ammo- 
pool t base extends invariably to the ammonia-cobalt base 
“The chlorplatinate of Purpureocobalt has the formula 
5NH:3.Co2Cls+2PtCle 
48 the following analyses show : 
06765 SO2 and the platinum ipitated as sulphid 
y rNcO Soe yee ae HCl) gave ‘ner gra of platinum = = 3351 
be os cent, 
09521 gr. gave 03169 grs. of platinum and 02488 grs sulphate of cobalt = 
8 per cent cobalt. 
i pi gave —— grs, of chlorid of silver = 41°80 per cent chlorine. 
The formula requires 
‘Eqs. Calculated. Found, 
Cobslt (a. 8 10°10 9-98 
Platine, oo 33°50 33°51 
Chloring,- - 7 42°01 41:80 
This galt is identical with the chlorplatinate described and 
analyzed by Claudet, and for which that chemist found the same 
