A Comprehensive Treatise on Inorganic and Theoretical Chemistry

PLATINUM 405
tion of brown flecks, and of platinum. It can be recrystallized from water, or from
dil. sulphuric acid. F. Hoffmann reported platinic dihydroxylaminediammino-
SUlphate, [Pt(NH8)2(NH20H)2](S04)2, by the action of the corresponding chloride
on silver sulphate, or by the action of the theoretical amount of sulphuric acid on
the oxalate. The yellow, prismatic crystals are soluble in water at ordinary temp. ;
the soln. becomes turbid at 30°. P. T. CIeve described platinic nydroxyacetatotetramminosulphate,
[Pt(NH3)4(OH)(C2H302)]S04.l|H20. W. J. Pope and
S. J. Peachey prepared trimethyl platinic sulphate, {(CH3)3Pt}2S04.2H20, by the
action of dil. sulphuric acid on the corresponding hydroxide.
As in the case of the hydroxychloroplatinic acids, H2Pt(OH)6_wCln, so with
the basic platinic sulphates, there may be a series of hydroxysulphatoplatinic
acids involving H2Pt(OH)4SO4, H2Pt(OH)2(S04)2 and H2Pt(S04)3. The soln. of
platinum in sulphuric acid, free from nitric acid, was found by E. Prost to deposit
a brick-red powder 4Pt(OH)4.Pt(OH)2S04.3H20 ; and R. Ruer obtained a
chocolate-brown powder, PtO2.3Pt(OH)4.Pt(OH)2SO4, containing a small proportion
of a platinous salt. There is nothing here to establish the chemical individuality
of the products. As indicated above, E. Davy obtained a black mass, by the action
of fuming nitric acid on platinic sulphide, which approximated in composition to
platinum dioxysulphate. PtO2SO4, and E. Prost obtained 4Pt(OH)4-Pt(OH)2SO4.
3H2O from cold soln., and Pt8O13SO4.16H2O from boiling soln. M. Blondel said
that no such compound as PtO2SO4 has been proved to exist.
According to M. Blondel, at 0°, hydrated platinic oxide dissolves slowly in
sulphuric acid, diluted with its own vol. of water, and there separates from the
soln. orange-yellow, microscopic needles of tetrahydroxysulphatoplatinic acid,
H2Pt(OH)4(SO4).H2O. He said that this represents the composition of what is
usually designated normal platinic sulphate. This compound is not soluble in
water, and it is decomposed forming free acid and hydrated platinic oxide;. It
loses 3 mols. of water at 100° to form hydrodioxysuphatoplatinic acid, H2PtO2(SO4),
which is soluble in water and easily polymerized. Some basic ammines are indicated
above.
I. I. TscherniaefE and A. N. Fedorova prepared platinic chloroethylenediaminotriamminosulphate,
[Pten(NH3)3ClJ2(S04)3, from the corresponding chloride ; and
A. P. Smirnoff, platinic trispropylenediaminosulphate, LP^C3H6.N2H4)3|(S04)2.
J. Gros, and W. Palmaer prepared platinic dichlorotetramminosulphate,
[Pt(NHj)4Gl2JSO4, by treating the corresponding nitrate or chloride with warm,
dil. sulphuric acid, or with sodium sulphate. Crystals of the dihydrate separate
out on cooling. The dihydrate loses no water over sulphuric acid, but at JOO°,
J. Gros, and P. T. Cleve obtained the anhydrous salt. C. Weltzien, and C. Gerhardt
also obtained the anhydrous salt, as a crystalline powder, by the action of cone,
sulphuric acid on the corresponding nitrate. According to P. T. Cleve, the
anhydrous salt is sparingly soluble in hot and cold water ; and C. Grimm found
the dihydrate to be sparingly soluble in cold water, and freely soluble in hot water ;
it can be recrystallized by cooling hot soln. ; nitric and hydrochloric acids form the
corresponding salts. Barium salts precipitate the sulphate ; and silver salts
produce a turbidity with aq. soln. which have been boiled for a long time. P. T. Cleve
prepared platinic chlorosulphatotetramminosulphate, [Pt(NH3)4Cl(S04) J2SO4, or
[Pt(NH3)4Cl2]S04.[Pt(NH3)4(S04)]S04, by the action of sulphuric acid on the
phosphatotetramminochloride. P. T. Cleve prepared platinic hydroxysulphatotetramminochloride,
[Pt(NH3)4(OH)(SO4)JCl.2H2O, by treating the sulphate with
one-third molar proportions of barium chloride. The colourless or pale yellow,
4-sided prisms of the dihydrate become anhydrous at 100° to 110°. At a higher
temp, the salt is decomposed. It is soluble in cold, and very soluble in hot water.
Ammonium sulphide gives a dark brown precipitate ; cone, soda lye dissolves the
salt and no ammonia is evolved when the liquid is boiled ; hydrochloric acid forms
dichlorotetramminochloride ; barium chloride, and sodium phosphate give no
precipitates ; silver nitrate forms a precipitate at once ; ammonium oxalate forms