796 



Dr. Gr. Rudorf on the Molecular and 



Argon. — Using the experimental results of Ramsay and 

 Travers (Proc. Roy. Soc. lxiv. p. 183 (1898)), the density of 

 pure argon is p = 0*001782. Here again the volume of the bulb 

 is incorrect. It should be 160*17 c.c. instead of 163*19 c.c. 

 or of 163*17 in the Phil. Trans, paper. 



Krypton and Xenon. — The densities of these gases, carefully 

 fractionated, have been redetermined by Moore (J. C. S. xciv. 

 p. 2181 (1908)), and from the data published by him we 



get for 



Krypton £ = 0*003709, and for 



Xenon p = 0*005842 * 



as compared with 0*003644 and 0*00572 originally obtained 

 by Ramsay and Travers (Phil. Trans. I. c). 



We have now all the data necessary for the calculation of 

 G and O :— 



Density of Helium ... p = 0*0001769 



Neon p = 0*00089 



Argon ... ^ = 0*001782 

 Krypton... p = 0*003709 

 Xenon ... p = 0*005842 



And using these values, we obtain the following results : — 

 Molecular Velocities. 





He. 



Ne. 



A. 



Kr. 



X. 



Go cm./sec 



1311 Xl0 4 

 1208 XlO 4 



5-845X10 4 

 5-385X10 4 



4-13 XlO 4 



3-806 XlO 4 



2-86 xlO 4 

 2-64 XlO 4 



2-28x10-1 

 2-10 XlO 1 



Qq cm./sec 







Some previous calculations are tabulated below. 



Author. 



Reference. 



Helium. 



Argon. 



Density. 



G. 



a. 



Density. 



G. 



Q. 



O. E. Meyer. 

 R. Schmidt. 

 J. H. Jeans. 



Die kinetische 

 Theorie der Gase. 

 2te Aufl. p. 194 

 (1899). 



IJeber die Diffu- 

 sion von Argon 

 und Helium. Dis3. 

 (1904). 



The Dynamical 

 Theory of Gases, 

 p. 113(1904). 



0-000191 



0-00017697 



1-98 

 (0 2 =16) 





11-62 xlO 4 

 12-077 XlO 4 



0-0017810 

 0-0017822 





3-81 X 10 4 | 

 3-806x10* 





13-11 xlO 4 





19-9 



413xl0 4 





(0,=16) 







