A Comprehensive Treatise on Inorganic and Theoretical Chemistry

398 INORGANIC AND THEORETICAL CHEMISTRY
lockere Vcrbindung of platinic and hydrogen sulphides, which loses its hydrogen
sulphide when washed with hot water. K. A. Hofmann and F. Hdchtlen obtained
dark brown platinic dihydrotrisulphide, PtS2-H2S, or PtS(HS)2, or H2PtS3, by
the action of dry hydrogen sulphide on a soln. of platinic chloride in absolute
alcohol, and washing the product with carbon disulphide to remove free sulphur.
U. Antony and A. Lucchesi obtained platinic hydrosulphide, Pt(HS)4, or
PtS2.2H2S, by the first action of hydrogen sulphide on a dil. soln. of hydrochloroplatinic
acid at ordinary temp., the continued passage of the gas produces some
decomposition. P. Schtttzenberger prepared platinic thiocarbide, S : Pt: C : Pt: S.
R. Bdttger observed that boiling aq. ammonia, and ammonium sulphide have
no perceptible action on the sulphide. J. Ribau observed that the sulphide is
insoluble in ammonium or alkali sulphides or polysulphides ; and P. de Clermont,
that it is insoluble in boiling soln. of ammonium salts. J. J. Berzelius' preparation
dissolves completely in aq. soln. of alkali sulphides or hydroxides forming platinum
and alkali thiosulphates. R. Bottger observed that platinic sulphide is decomposed
when it is kneaded with potassium at ordinary temp., and intense combustion
occurs ; sodium does not act until it is warmed. Boiling soln. of potassium
hydroxide, or sodium carbonate do not act on the sulphide. E. Davy said that the
sulphide is decomposed when heated with zinc, or when fused with potassium
chlorate, or hydroxide, and, added R. Bottger, with potassium nitrate. W. Skey
obst»rved that platinum disulphide reduces auric chloride.
C. Wirissinger obtained a colloidal solution of platinic sulphide by dialyzing
the liquid obtained by the action of hydrogen sulphide on a very dil. soln. of a
platinic salt. U. Antony and A. Lucchesi employed a 3 per cent. soln. of hydrochloroplatinic
acid, or sodium chloroplatinate at 15° to 18°. G. Hofmeier employed
50 c.c. of a 1 : 1,000 aq. soln. of platinic chloride, diluted it to 20O c.c. and
passed the gas for a short time at 50° to 60°, and dialyzed the liquid. J. C. H. Heyer,
and T. Svedberg added yellow soln. of ammonium sulphide to a soln. of platinic
chloride. G. Hofmeier recommended gum arabic as a protective colloid. The
colloidal soln. is brown or brownish red in transmitted light, and dark grey in
reflected light. The colloidal sulphide is coagulated by heat, by evaporation, by
hydrochloric acid, alkali chlorides, barium sulphate, and animal charcoal.
According to J. J. Berzelius, platinic sulphide precipitated by hydrogen sulphide
dissolves in ammonium sulphide to form a reddish-brown soln. of what was thought
to be ammonium sulphoplatinate, (NH4)2PtS3. The liquid—possibly a colloidal
soln.—deposits platinic sulphide when treated with acids. K. A. Hofmann and E.
Hdchtlen prepared ammonium polysulphoplatinate, (NH4)2PtS3.S12.2H20, by
saturating a 25 per cent. soln. of ammonium sulphide with sulphur at 30°, and
dropping the liquid, with constant stirring, into a cold, 10 per cent. soln. of platinic
chloride. The reddish-brown precipitate is allowed to stand in a closed vessel for 2
or 3 days at 5°, filtered by suction, washed with carbon disulphide, and dried some
hours in vacuo over sulphuric acid. The red, rhombic pyramids are stable when
dry ; they are insoluble in ether ; and form a yellowish-red soln. with alcohol.
J. J. Berzelius obtained a green mass—possibly potassium sulphoplatinate, K2PtS3,
when potassium disulphide is fused in a platinum crucible. The aq. soln. deposits
platinic sulphide. Precipitated platinic sulphide is soluble in aq. soln. of potassium
sulphide ; and similarly also with sodium sulphide, and as indicated above, it is
possible that the soln. contains sodium sulphoplatinate, Na2PtS3. The preparation
of L. N. Vauquelin, and J. Persoz, indicated above in connection with platinic
sulphide, may have contained sodium sulphoplatinate.
F. W. Semmler prepared platinic disulphovinylsulphine, [Pt{(C2H3)2S}S2], and
platinic disulphovinylsulphinechloroplatinite, [Pt{C2H3)2S}S2l.2(C2H3Cl)PtCl4 ;
T. Wertheim, platinic disulphoaUylsulphine, [Pt{(C3H5)2S}S2] ;—vide the sulphine
salts of the halides, etc.
According to J. J. Berzelius, moist, precipitated platinic sulphide when exposed
to air forms sulphuric acid, and in many respects behaves like J. W. Dobereiner's