I' 



ON AMMONIACAL PLATINUM BASES. 55 



If PtsljvrH 3 NH 2 H }0 De ^he formula of the hydrate, it is the anhydro-hydrate of a 

 !oh 

 new base: Diplatosemidiammine. 



When the alkaline liquid, with which the chloride had been boiled, was separa- 

 ted from the hydrate, it had a yellowish eolour. It was neutralised with hydrochloric 

 acid, when a voluminous precipitate, of a dirty green eolour, was thrown down, and 

 afterwards the chloride of platosemidiammine crystallised l ). The green curdy precipi- 

 tate was washed with large quantitees of boiling water, which extracted the chloride 

 of platosemidiaramine, and finally left undissolved a black uncrystalline powder, which 

 is the anhydro-chloride of diplatosemidiammine. When formed by the action of hy- 

 drochloric acid, it seems most likely that the chloride of platosemidiammine, obtained 

 by adding hydrochloric acid to the alkaline solution, originates from diplatosemidiam- 

 mine, but the solution might also possibly, contain hydrate of platosemidiammine. 



On one occasion I tried adding an excess of the hydrate of sodium to a boiling 

 solution of the chloride of platosemidiammine; the reaction was the same, as when I 

 employed the chloride in its undissolved form, but the quantity of the anhydro-hy- 

 drate of diplatosemidiammine thus obtained was very small. 



fOB 



|NH 3 "NH, . Hl ~ 



JJerivates of the hydrate r t. NH -- NH H j O 



>0H 



1. Action of hydrochloric acid. If treated with hydrochloric acid the hydrate 

 tirst assumes a black eolour, which merges after some tiine into a dirty yellow. The 

 yellow produet, obtained by different preparations, did not show a constant composition. 

 It Avas boiled with large quantities of water, that dissolved some chloride of platose- 

 midiammine and left a black uncrystalline powder. This produet was dried at 100° in 

 the air-bath and subjected to the following analysis. 



0,4980 gr. gave 0,3i>70 gr. metallic platinum and 0,l'hso gr. chloride of silver =0,0712 

 gr. chlorine. 



Calculated in pr. et. we have: 



Platinum 73,69 



Chlorine 14,29 



The same composition also belongs to the black produet, obtained by adding 

 hydrochloric acid to the alkaline solution, with which the chloride of platosemidiam- 

 mine had been treated. 



The compound obtained in the latter manner gave, on analysing, the following 

 quantities: 



1. 0,6900 gr. gave 0,5ior» gr. metallic platinum and 0,3790 gr. chloride of silver 

 = 0,0937 gr. chlorine. 



') It was subjected to au analysis, which gave 65,47 p. et. platinum and 23,52 p. et. chlorine; calcutated pla- 

 tinum 65,35 chlorine 23,42. With nitro-muriatic acid the compound also gave hexagonal or rhombic 

 scales. 



