ON AMMONIACAL PLATINUM BASES. 37 



The formula requires: 



Calculated Found 



Gerhardt Cleve 

 (raean) 



Platinum 197,88 — 46,46 46,31 46,96 (a) 



Nitrogen 56,00—13,15 13, oo 13, is (b) 



Hydrogen 12,00 — 2,82 2,93 3,15 (c) 



Oxygen 160,ou— 37,57 37, 83 36,74 



425,88 100,oo 100,oo 100,oo 



The nitrate dissolves without difficulty in hot water and recrystallises from the 

 solution on cooling. Hydrochloric acid mixed Avith the solution gives yellow octahed- 

 ral crystals and bichromate of potassium yields a cinnabarine-red precipitate. 



6. Nitrato-nitrite ^'oPnh o no was °btained by boiling the nitrite of pla- 

 tosammine with nitrie aeid. Red vapours are evolved and if the solution is evapora- 

 Ted and left to crystallise in a warm place, it yields large square colourless tablets. 



Analysis the compound dried över sulphuric acid: 



a. 0,4075 gr. gave 0,1795 gr. metallie platinum. 



b. 0,2730 gr. gave 43,5 C. C. nitrogen (temp. of the water 15°. Bar. 763 m. in. 

 t. 18) =0,0509 gr. nitrogen 



c. 0,2787 gr. gave 44 C. C. nitrogen (temp. of the water 18°. Bar. 763 m. m. 

 t. 18°). =0,05079 gr. nitrogen. 



d. 0,3290 gr. gave 0,0430 gr. water = 0,oo'»8 gr. hydrogen. 



The formula requires: 



Calculated Experiment 



a bed 



Platinum 197,88 — 44,18 44,05 — — — 



Nitrogen 84,oo — 18,76 — 18,65 18,22 — 



Hydrogen ... 6,oo — 1,34 — — — 1,46 



Oxygen 160,00—35 ,72 — — (36,".;) 



447,88 100,90 



The nitrato-nitrite when heated to 100° does not chano;e its weight. If the so- 

 lution of the salt is precipitated with iodide of potassium, a black powder containing 

 26,13 p. et. platinum is thrown down. The iodide of platinammine contains 26,74 p. et. 

 platinum. 



7. Chloro -nitrato-nitrite " c y }Pt{ NH 3 ' ' N0 ' When some hydrochloric acid was 

 added to a verv concentrated solution of the preceding (N:o 6) compound, small colour- 

 less rhombic scales were obtained. They are easily dissolved in water. 



Analysis the compound dried at 100°: 



0,3880 gr. gave 0,i8io gr. platinum and 0,1355 gr. chloride of silver =0,0335 gr. 

 chlorine. 



