582 PROFESSOR DITTMAR AND MR JOHN M'ARTHTJR ON 



Supplement to Experiment Ya. of First Series. 



Of the 12 grins, of chloroplatinate produced in this experiment, the greater 

 part was used for the following experiments : — 



6*2356 grms. of chloroplatinate, dried at 110°, was dissolved in about 

 250 c.c. of boiling water in a platinum basin, and the solution allowed to stand 

 (for about 40 hours), when a large crop of crystals was found to have separated 

 out. These were washed thrice with small instalments of water and put aside 

 as " Crystals C." The mother-liquor was distilled down, in a flask provided 

 with a ground-in alembic and attached to a Liebig's condenser, to about 

 25 c.c. The distillate contained a small quantity of hydrochloric acid, which 

 was determined gravimetrically by nitrate of silver ; its chlorine amounted to 

 0-87 mg. 



The contents of the flask, on cooling, deposited a crop of crystals which 

 were collected and put aside as " E," the mother-liquor being labelled " D." 

 Each of the products was analysed in toto (by reduction by hydrogen in the 

 wet- way) so as to obtain the absolute weights of platinum, &c. 



Crystals " C." 



Substance unweighed. Platinum 1-9329. Total chlorine* 2*07648 and 

 2-07725 ; mean, 207686. Fixed chlorine 0*46467 and 046450 ; mean 0*464585 

 per fraction analysed. For the whole 0*701157. 



Hence per 2KC1 parts : — 



Platinum. Loose Chlorine. Oxygen (calculated). 



195*48 139-129 



or 39241 x 01 00759 x \ O 



About 2 per cent, of the loose chlorine is replaced by oxygen. 



Crystals "E" 



Fixed Chlorine. Loose Chlorine. Flatinum. Oxygen. 



Absolute weights, 0-15260 029754 0-4195 



Relative „ 70-91 138-26 194-93 



= 3-8996x01 01004x| O 



Mother-liquor " D" 



Platinum. Fixed Chlorine. Loose Chlorine.t 



Absolute weights, . 0-1441 0-U5041 0-11940 



Relative „ 195-00+ 68-253 161-58 



or 1-9250x01 or 4-5574x01 



Hence, for the composition of the solution (if we take Pt = 195, as we 



* The AgCl in the titrations had a tinge of pink indicating platinum, 

 f Including the 0'87 nig. from the distillate. 

 % Instead of 194-93, as found for "E." 



