ATOMIC WEIGHTS 289 



This, combined with previous determinations, gives — 



Berzelius 43.134, ± .0142 



Weibull 43.150, ± .0207 



Bailey 43.372, ± .0056 



General mean 43.317, ± .0051 



Venable ^ determined the atomic weight of zirconium b}' analysis of the 

 oxychloride, ZrOCU-SHoO. This compound was purified by crystalliza- 

 tion from hot hydrochloric acid and dried in a stream of hydrochloric 

 acid gas. It was then dissolved in Avater, and after evaporating the 

 solution to dryness in a platinum crucible the residue was converted into 

 zirconia by prolonged ignition. The data are subjoined : 



Mean, 52.986, ± .0085 



Hence Zr = 90.805. 



For computing the atomic weight of zirconium we now have the sub- 

 joined ratios: 



(1). Percentage ZrO, in ZrCSOi):, 43.317, ± .0051 



(2). Percentage ZrO^ in ZrCSeO,)^, 32.558, ± .0192 



(3). Percentage ZrO, from K,ZrFe, 43.200, ± .043 



(4). Percentage K.SO, from K^ZrFe, 61.365, ± .094 



(5). Percentage ZrO, in ZrOCU.SH^O, 62.986, ± .0085 



(6). K,S04:ZrOo: : 100: 70.396, ± .0079 



The antecedent values for reduction are — 



CI = 35.4584, ± .0002 K = 39.0999, ± .0002 



S = 32.0667, ± .00075 F = 19.041, ±.00135 



Se = 79.176, ± ,0029 H = 1.00779, ± .00001 



1 Journ. Anier. Chem. Soc, 20, 119. 1898. 



