44 ATOMIC WEIGHT DETERMINATIONS. 



E. Peligot : 5248 (0 = 16) ; 328 (0 = 100). 



Peligot reached this value by a careful carbon determina- 

 tion of chromous acetate, produced by precipitating a dilute 

 solution of chromium protochloride with sodium acetate, 

 C = 75. Peligot does not regard the experiment as defini- 

 tive, the salt possessing but little stability. {Annal. de 

 Chimie et de Physique, (3,) 12, 1844, 527.) 



K J. Berlin : S2.S4. (O = 16) ; 328.39 (O = 100). 



Five experiments were made on the decomposition of 

 argentic chromate with chlorhydric acid and alcohol. The 

 silver chloride was washed in the flask in which it was pre- 

 cipitated, treated with aqua regia, melted and weighed with- 

 out removal. The decanted fluid and the wash-water were 

 evaporated to dryness with excess of ammonia, treated with 

 water and the chromium oxide filtered otF, heated to redness 

 and weighed. [Nothing is said of the recovery of any 

 argentic chloride that might have been removed by the 

 decantation.] The value taken is calculated from the com- 

 parison of the amounts of argentic chloride and of chro- 

 mium oxide obtained, Ag = 1349.66; CI = 443.28. The 

 extreme diflference is 1, for O = 100. The argentic chro- 

 mate was prepared by adding nitrate to a solution of potassic 

 chromate. [Erdmann's Journ. fiir Prak. Chem., 38, 1846, 

 145.) 



V. A. Jacquelin : 50.08 (0 = 16) ; 313 (0 = 100). 

 By washing and purifying violet chromium chloride, 

 Jacquelain obtained a substance which he took to be the 

 pure chloride and which was more soluble than the un- 

 puritied salt. He analysed it by melting with soda, and 

 arrived at the above number. [Liebig's Annal., 64, 1847, 

 275 ; Pevue Scient, 11,,, 198.) 



A. Moberg: 53.563 (O = 16); 334.769 (O = 100). 



Moberg made twelve experiment^ on the decomposition 

 of chromium salts by heat. In two cases the sulphate 

 dried at a low red heat was decomposed by strong ignition 

 in a platinum crucible ; the results being, 335.65 and 335.29 

 for chromium. Ten experiments were made on the decom- 

 position of ammonium-chromium-alum which had been 

 dried in a pulverized state for a long time. These deter- 

 minations gave from 333.965 to 335.739. The value taken 

 is the mean. The alum employed was prepared from pure 

 materiid, and was repeatedly recrystallized. S = 200 ; X = 

 87.5. {Erdmann's Journ. fiir Prak. Chem., Iy3, 1848, 115.) 



