RHODIUM. 313 



RHODIUM. 



Berzelius * determined the atomic weight of this metal by the analysis 

 of sodium and potassium rhodiochlorides, Na 3 RhCl 6 , and K 2 RhCl 5 . The 

 latter salt was dried by heating in chlorine. The compounds were ana- 

 lyzed by reduction in. hydrogen, after the usual manner. Reduced to 

 percentages, the analyses are as follows : 



In Na,RhCl 6 . 



Rh. 3 NaCl. <T/ 3 . 



26.959 45.853 27.189 



27.229 45-3 01 27.470 



...... ...... 27.616 



Mean, 27.094 Mean, 45.577 Mean, 27.425 



In K 



Rh. 2KCI. CI 3 . 



28.989 41-450 29.561 



From the analyses of the sodium salt we get the following values for 

 Rh: 



P'rom per cent, of metal .................... Rh = 104.191 



From per cent, of NaCl .................... " = 102.449 



From per cent, of C1 3 ..................... " = 105.103 



From ratio between C1 3 and Rh ......... ..... " = 104.263 



From ratio between NaCl and Rh ...... ..... " = 103.544 



These are discordant figures ; but the last one fits in fairly well with 

 the values calculated from the potassium compound, which are as 

 follows : 



From per cent, of metal .................... Rh 103.499 



" From per cent, of KC1 ..................... " = 103.648 



From per cent, of C1 3 ...................... " = 103.485 



From Rh : C1 3 ratio ........................ '- = 103.495 



From Rh : KC1 ratio ....... . ............. " = 103.540 



Mean Rh = 103.533 



If = 16, this becomes Rh = 104.323. 



Jorgensen's determination,! so far as I can ascertain, was published 

 only as a preliminary note, to the effect that the atomic weight of rho- 

 dium is 103, nearly. No details are given. 



* Poggend. Annalen, 13, 435. 1828. 

 t Journ. fur Prakt. Chem. (2), 27, 486. 



