Section III.. 1909. [ 7S ] Tuans. R. S. C. 



V. — A Note on the SoluhUifij of the Radioactive Emanations in Licpiids. 



By R. W. Boyle, M.Sc, Ph.D. 



(Comnninicated by H. T. Baknes, D.Sc, and read :May 26, 1909.) 



From the work of von Traubenberg, we have the fact that Henry's 

 law is applicable in the case of the solution of radium emanation in a 

 liquid. In this sense a " coefficient of absorption " can be defined 

 and its numerical value can be determined experimentally. 



If an enclosure be partly filled with a liquid, the rest of the space 

 being occupied by a gas, and initially either the liquid or the gas be 

 activiated with emanation, after intimate contact between the liquid 

 and the gas has been established for a certain time there will be a 

 definite distribution of emanation between the two phases. If k be 

 the concentration of the emanation within the liqiiid, and K the con- 

 centration within the gas, after equihbrium has been established the 

 ratio of these concentrations, viz. k/K, will be the coefficient of ab- 

 sorption. 



The definition is based on the form of Henry's law "that a liquid 

 continues to absorb a gas until equilibrium between the partial pres- 

 sures of the gas in the two phases is produced." Hence, when the 

 temperature is kept constant, the value of the coefficient depends only 

 upon the nature of the absorbing liquid and not on the pressure or 

 nature of the gas in contact. The value of the coefficient must of 

 course decrease with rising temperature. 



Values of the coefficient for various liquids when absorbing 

 radium emanation have been determined by von Traubenberg/ 

 Himstedt,' Mache,' Hofmann,* Mache and S. Meyer,^ and KoflSer*. 



At ordinary temperatures perhaps the best value for water is 0.22 

 and for petroleum 10.2 (Hofmann). The oils from petroleum are the 

 best known liquid absorbers. Von Traubenberg places the following 

 liquids in this ascending order of absorptive power: 

 Solution of Copper Sulphate 

 Water 

 Paraffin oil 

 Alcohol 



Petroleum ether 

 Nitrobenzol 

 " Kaiserol." 



' Phys. Zeit., 5, 130, 1904. * Phy. Zeit., 6, 337, 1905. 



^ Phys. Zeit., 5, 210, 1904. » p^y Zeit., 6, 692, 1905. 



3 Wiener Ber., .-13, 1329, 1904. « Phys. Zeit., 9, 6, 1908. 



