M. C. Lea on the Platinum Metals. 249 
of ammonia alone, which produces a pale straw color—in both 
cases a very dilute solution is supposed to be used. 
and the color deepens to a rich wine brown. 
Protochlorid of Palladium.—To apply the test to this metal, 
communicate a pale lemon color only, to the liquid. By boiling, 
this rapidly darkens to a wine brown shade, increasing in in- 
tensity until it finally appears black. Dilution however shows 
that this results from its intensity only ; the diluted liquid is clear 
from troubling, and has a warm brown tint. 
Detection of Ruthenium in Presence of Iridium by Hyposulphite of Soda 
ae and other Reagents. 
For the following examinations, solutions of sesquichlorid of 
ruthenium and of chloriridiate of ammonium were used. Both 
in a state of perfect purity were weighed dry, dissolved, and 
ixed in the following proportions: 
Ru,Cl,, 1 part; chloriridiate of ammonium, 10 parts. 
The hyposulphite test was not in any way impaired by the 
resence of iridium. : 
Sulphocyanid test gave a red coloration, but much less clear 
than in the absence of iridium,’ and much inferior to the 
reaction with hyposulphite. — san : 
Acetate of lead ‘ ded and boiled gave a precipitate, in 
which the purplish shade characteristic of ruthenium was 
very evident. = 
aN 3) 1 part; eee 20 agar 
yposulphite gave a periect reaction. : 
Salpline paid eddie brows coloration and unsatisfactory. 
Acetate of lead gives a precipitate still distinctly colored 
by ruthenium. It is to be regretted that to judge cor- 
: is test fails when the Ru is in proportion to the Ir less 
“Sorging A ung. pe tomate 1 ; Rahs ie A sooalsiivt ene ea 
e i i ; of Ir. 
sro eile oe aac Stall 
~ Ast. Jour. Scr.—Secoxp Sunres, Vou. XXXVI, No. 113.—Szrr., 1964 
32 
