OX AMMONJACAL PLATINDM BASKS. i.) 



The analysis gave more platinurn and less carbon than required by the formula. 

 This was caused by a small mixture of the chloride of platosammine, as I afterwards 

 found Still there can be no uneertainity as to the eorreetness of the formula. 



With oxalie acid the solution of the chloride gives a heavy precipitate of lhom- 

 bohedral crystals, and with chloroplatinite of potassium a double chloride analogons to 

 the green chloride of Magnus. When the chloride was boiled with a solution of i odide 

 of potassium a strong stnell of aniline was emitted and a yellow powder precipitated. 

 This powder was found by analysis to contain 40, dj p.et. platinum, being consequently 

 the iodide of plotosammine, which contains 40,7:; p.ct. platinum. The yellow powder 

 contained a small quantity of aniline. 



2. Chloroplatinite, RCL^CLPt, is thrown down by mixing hot, concentrated so- 

 lutions of the chloride (N:o 1) and of chloroplatinite of potassium. The double chloride 

 is immediately precipitated in the form of a chamois-coloured, glittering powder, which 

 seems, examined with the microscope, to be composed of needles arranged like feathers. 

 The compound is very little soluble. 



Analysis: 



O,;!:':' gr. (dried at 100°) gave 0,i'i:.r gr. platinum and 0,3H8 gr. chloride of silver 

 =0,0/78 gr. chlorine. 



The formula requires: 



Theory Experiment 



Platinum 52, vi 52,33 



Chlorine 18,72 18,87 



3. Nitrate, R . 2 . 2N0 2 , is formed if aniline, mixed with some aleohol, is added 

 to a boiling hot solution of the nitrate of platosammine. On cooling the compound 

 crystallises into thin, colourless or faintly rose-eolored, almost square seales. The ni- 

 trate is easily soluble in hot water and crystallises on refrigeration of the solution. 



Analysis: 



a. 0,tifi:! gr. gave 0,1528 gr. platinum. 



b. 0,4860 gr. gave 67,5 C. C. nitrogen (temp of the water 17°. Dar. 773 m.m. t. 

 16°) =0,0794 gr. nitrogen. 



The formula requires: 



Theory Experiment 



Platinum 36, .v.' 36,70 • 



Nitrogen 15, 50 l(!,:ii 



4. Sulphate, R . O.. . SO., is obtained by adding aniline to a boiling solution of 

 the sulphate of platosammine. The compound soon separates in thin and almost colour- 

 less rhombic seales. 



