Oil the Aciiofi of Acetone on Bichloride of Platinum, 85 



I have likewise obtained a considerable quantity of this sub- 

 stance by keeping, for 24 hours, a mixture of acetone with 

 the bichloride in a well-closed vessel. I call this substance 

 Metacechlorplatin. 



Metacechlorplatin is of a sulphur yellow colour; the cry- 

 stals are small and difficult to measure. It is very nearly 

 without any smell. After having been dried in the air, it 

 loses nothing in weight when placed in a vacuum over sul- 

 phuric acid, whether at common temperatures or raised above 

 100°. It inflames very easily, and burns with a partially 

 green flame, leaving a silvery white residue of platinum. 

 Heated in a retort it blackens, and without swelling up it 

 gives out abundance of vapours, which are at first peculiar, 

 but afterwards smell strongly of muriatic acid; a part, at 

 least, of these vapours easily condenses into an oily substance. 

 The carbonaceous residue burns slowly in the open air, like 

 tinder, and leaves a residue of silvery white platinum. At 

 common temperatures it is almost wholly insoluble in water; 

 when heated in it, it forms a yellow solution, which, however, 

 contains only a very little of the salt. When boiled, this 

 solution threw down a brown flocculent substance, whilst 

 that portion which was not soluble was changed into a brown, 

 slimy mass without any visible appearances of metallic plati- 

 num. It seems to be quite insoluble in aether. At common 

 temperatures alcohol acts but little upon it, but when heated 

 it dissolves a portion, acquiring at the same time a yellow 

 colour, on cooling a yellow crystalline powder is deposited. 

 Muriatic acid, even the most concentrated, dissolves it only 

 at higher temperatures; the acid solution may be raised to 

 the boiling point without visible change. A solution of caustic 

 potassa easily dissolves metacechlorplatin, forming a brown 

 solution. Solutions of chloride of potassium or sodium, when 

 heated, also dissolved it, and the yellow solution underwent no 

 change on boiling. The determination of the quantities of 

 carbon and hydrogen in metacechlorplatin was made by burn- 

 ing one portion with oxide of cojiper, and another portion with 

 chromateof lead. Its composition ( PI. Cl^ + C H'° O) shows 

 by comparing it with that of acetone, (C^ H'- 0-), that in it one 

 atom of the protochloride of platinum replaces H"^ O. As how- 

 ever there appears to be formed at the same time several other 

 combinations of chlorine, the action is probably not so simple. 

 Certainly it is probable that a combination takes place of 

 2 atoms of chlorine with 2 atoms of hydrogen as in the action 

 of bichloride of platinum on alcohol, and in this case there is 

 formed likewise through the action of 1 atom of oxygen, one 

 of the compounds resembling aldehyde (see my paper on the 



