A Comprehensive Treatise on Inorganic and Theoretical Chemistry

268 INORGANIC AND THEORETICAL, CHEMISTRY
does not dissolve the salt, but with boiling alcohol, platinum is formed. A boiling
soln. of sodium hydroxide does not split off ammonia, but it forms a black explosive
product. S. M. Jorgensen, and A. Cossa prepared pale brown crystals of silver
amminotrichloroplatinite, Ag[Pt(NH3)Cl3], by the action of silver nitrate on the
potassium salt. A. Cossa observed that an excess of silver nitrate in cold soln.
of potassium amminotrichloroplatinite precipitates two-thirds of the chlorine as
silver chloride, and with boiling soln., all the chlorine is precipitated. No sparinglysoluble
complex salts are formed by potassium amminotrichloroplatinite with
zinc, mercuric, or stannous chlorides. According to A. Werner, when an excess of
a hot soln. of the potassium amminotrichloroplatinite is mixed with potassium
amminopentachloroplatinite, a compound crystallizing in green leaflets is deposited
at a certain temp., but is converted into potassium amminotrichloroplatinite as
the mixture cools.
R. Uhlenhut 8 prepared platinous tetrahydroxylaminechloride, [Pt(NH^OH)4]-
Ci2, by dissolving a gram of the hydroxide in 5 c.c. of boiling, dil. hydrochloric acid ;
W. Losscn, by warming a soln. of hydroxylamine hydrochloride with platinous
chloride, concentrating by evaporation and cooling ; and F. Hoffmann, by the action
of an excess of hydroxylamine on platinous cis-dichlorobispyridine. H. Alexander
made it by shaking platinous chloride with an excess of hydroxylamine, triturating
the grey or brown product with cold hydrochloric acid, dissolving the mass in
water, and precipitating with alcohol or with a current of hydrogen chloride ; and
also by mixing a IO per cent. soln. of potassium chloroplatinite (1 mol.) with solid
hydroxylamine hydrochloride (4 mols.), and then adding alkali carbonate. After
the soln. has stood some time, add alkali-lye (2 mols.), dissolve the precipitate in
the theoretical proportion of cold, dil. hydrochloric acid, and precipitate the salt
from the filtered soln. by adding alcohol or passing hydrogen chloride through the
liquid. The white, acicular or tabular crystals detonate * when heated to about
110°. They are soluble in water and in ordinary alcohol, but, according to W. Lossen,
insoluble in alcohol. H. Alexander, and R. Uhlenhut said that the salt is insoluble
in cone, hydrochloric acid ; hydrobromic acid gives colourless needles of the
bromide ; sodium thiosulphate gives a white crystalline precipitate ; aq. ammonia,
or alkali-lye precipitates the hydroxide ; sodium carbonate or phosphate gives a
fine crystalline precipitate ; potassium chromate, a reddish-brown, amorphous
precipitate ; Kchling's soln., and auric chloride reduce the soln. ; silver nitrate does
not precipitate all the chloride ; and platinic chloride or hydrochloroplatinic acid
precipitates the platinous tetrahydroxylaminechloroplatinate, [Pt(NH2OH)4JPtCl4,
in blue or violet needles, which explode when heated above 100°. According to
H. Alexander, the salt is insoluble in water but sparingly soluble in hot water ;
insoluble in alcohol; soluble in hydrochloric acid, and the yellow soln. on a waterbath
furnishes the trans-salt [Pt(NH2OH)2Cl2] ; it dissolves with the development
of red fumes in nitric acid ; hydroxylamine converts it into platinous tetrahydroxylaminechloride
; and a suspension of the salt in water when treated with ammonia
forms a white precipitate.
According to H. Alexander, if the filtrate from the mixture of platinous chloride with
an excess of hydroxylamine be evaporated at a low temp., and treated with alcohol, a
white precipitate approximating platinous tetrahydroxylaminehydroxychlorlde,'[Pt(NH2OH)4]-
(OH)C1.2H20, is formed ; and platinous tristetrahydroxylaminetetrahydroxydlchloride,
2[Ft(NH2OH)4](OH)2-[Pt(NH2OH)4]Cl2, or [Pt(NH2OH)4](OH)2.2[Pt(NH2OH)](OH)Cl, is
produced in microscopic needles by adding the theoretical proportion of barium oxide to
a soln. of platinous chloride and hydroxylamine hydrochloride.
According to H. Alexander, if an excess of aq. ammonia be added to a soln. of
platinous £rans-dichlorodihydroxylamine, and the precipitate rapidly filtered off,
washed with cold water, dissolved in a little cold hydrochloric acid, filtered, and
mixed with cone, hydrochloric acid, with cooling, there is formed platinous transdihydroxylaminediamminochloride,
[Pt(NHg)2(NH2OH)2]Cl2 ; and the same
product is obtained by dissolving the corresponding hydroxide in a little cone.