44 P. T. C LE VE, 



Hydrate of sodiurn boiled with the chloride produces a dirty white powder, which 

 seems to be the hydrate of a peculiar base of platinum (see the following: »On the 

 products formed by the action of alkalies upon the chloride of platoseinidiammine».) 



2. Bromide RBr, is obtained by adding a solution of bromide of potassium to 

 the nitrate of platoseinidiammine. If the solutions are eoncentrated the liquid is soon 

 filled with shining, golden-coloured, needles. When placed upon a filter they are soon 

 changed to flat, brick-coloured, microscopical needles. The red needles again yield the 

 yellow bromide by recrystallisation from a boiling solution. 



Analysis: the bromide dried at 100°. 

 0,8460 gr. gave 0,4265 gr. metallic platinum and 0,8ioo gr. bromide of silver =0,3447 

 gr. bromine. 



The formula requires: 



Theory Experiment 



Platinum 197,88 — 50,49 50,41 



Bromine 160,00 — 40,83 40,74 



Ammonia 34,00 — 8,68 8,85 (loss 



391,88 100,oo 100,50 



The bromide is easily dissolved in ammonia and is then changed into the bro- 

 mide of platodiammine. It is easily combined with bromine and gives the bromide of 

 platinsemidiammine. 



3. lodide RI 2 If the eoncentrated solution of the iodide of potassium and the 

 nitrate of the base are mixed together, the liquid soon stiftens into fine, yellow, micro- 

 scopical crystals. The iodide dissolves but with difficulty in boiling water. With am- 

 monia it yields the iodide of platodiammine. Heated with nitromuriatic acid it gives 

 off violet vapours of iodine and the solution deposits, on cooling, microscopical rhom- 

 bic scales, ressembling the chloride of platinsemidiammine. The iodide is directly 

 united with iodine and produces the polyiodide of platinsemidiammine, crystallising in 

 small black octahedrons, sometimes having the appearance of hexagonal tablets under 

 the microscope. The formula of the polyiodide thus obtained is: 



|i 



Pt NH 3 'NH 4 I~I 2 

 1 1, 



Analysis: the iodide dried at 100°. 



a. 0,2455 gr. gave 0,0985 gr. metallic platinum. 



b. 0,3520 gr. gave 0.3355 ot. iodide of silver =0,1830 gr. iodine. 



The formula requires: 



Theory Experiment 



a b 



Platinum 197,88 — 40,73 40, 12 — 



Iodine 254,00—52,27 — 51,50 



Ammonia 34,00 — 7, 90 — 



485,88 100,oo 



