606 



PROFESSOR DITTMAR AND MR JOHN M'ARTHUR ON 



III. Set of Experiments. 



Subject, the same " 95 per cent." salt as was used in Sets I. and II. Method 

 the same as that used in Set I. ; except that the salts were made into sul- 

 phates only virtually, by addition of the calculated amount of standard sulphuric 

 acid. Platinum added on Finkenerising, = 25 c.c. or 1*25 times the calculated 

 minimum. 



Product (PtCl 6 K 2 and x E 2 S0 4 ) " recrystallised." 



Results. 



Experiment. 



I. Chloride of potassium taken, 

 ' II. Platinum obtained, 

 III. KC1 found if =76117 II, . 

 Error = 111. -I., . 



The ether-alcohol liquors not analysed. 



Uniting the four analyses into one, we have- 

 Chloride of potassium taken, 

 Platinum obtained, ..... 



Hence A : p. = 076116. 



(p:A) x K 2 Cl 2 = "Pt" = 195-99. 



1. 



2. 



3. 



4. 



75330 



75253 



75327 



75426 grm 



9900 



•9880 



•9902 



•9907 „ 



75356 



75204 



75371 



75409 „ 



+ 0-26 



-0-49 



+ 0-44 



-017 mg. 



= A = 3-0134grms. 

 = ^ = 3-9589 „ 



IV. Set of Experiments. 



The solutions analysed were such as to represent very nearly a salt consist- 

 ing of 82 per cent, of chloride of potassium, 15 of chloride of sodium, and 3 of 

 sulphate of magnesia. The quantity of chloride of potassium used was about 

 0"656 grm. per analysis. 



The solution to be analysed was mixed with the quantity of standard 

 sulphuric acid equivalent to the chlorides present, and 1*25 times the calculated 

 volume of platinum solution, and Finkenerised ; the resulting product being 

 " recrystallised." All else as in III. 



Results. 





Experiment. 





l. 



2, 



3. 



4. 



I. 



Chloride of potassium 



taken, 



•65390 



•65294 



•65032 



•65046 grm 



II. 



Platinum obtained, 



. 



•8597 



•8553 



•8543 



•8547 „ 



III. 



KG, corresponding 

 = 11x076117, 



. } 



•65438 



•65103 



•65027 



•65057 





Error, III. -I.,. 



• 



+ 048 



-1-91 



-0-05 



+ 0-11 mg. 



