LITHIUM. 89 



cuted with his usual wonderful accuracy. In three titra- 

 tions, in which all the weights were reduced to a vacuum 

 standard, the following quantities of LiCl balanced 100 

 parts of pure silver : 



39-356 

 39-357 

 39-361 



Mean, 39.358, ± .001 



In a second series of experiments, intended for determin- 

 ing the atomic weight of nitrogen, LiCl was converted into 

 LiNOg. The method was that employed for a similar pur- 

 pose with the chlorides of sodium and of potassium. One 

 hundred parts of LiCl gave of LiNOg : 



162.588 

 162.600 

 162.598 



Mean, 162.5953, ± .0025 



We have now the following ratios from which to deduce 

 the atomic weight of lithium : 



(l.) AgCl : LiCl : : lOO : 29.584, zt -0075 



(2.) Ag : LiCl : : lOO : 39.358, ± .001 



(3.) LiCl : LiNOg : : lOO : 162.5953, zb .0025 



(4.) Per cent, of CO^ in Li2C03, 59.420, ± .0057 



Hence two values for the molecular weight of LiCl : 



From (i) LiCl = 42.3187, 4= .0039 



From (2) " = 42.3787, rb .0111 



General mean " = 42.3720, ± .0037 



For lithium itself we get three values : 



From molecular weight of LiCl Li = 7.002, zfc .015 



From ratio (3) " = 7.0287, zb .042 



From ratio (4) " = 7.0085, zb .008 



General mean " = 7.0073, zb .007 



If = 16, then Li = 7.0235. Stas himself gives 7.022 

 as his determination. Difference, .0015. 



