76 



THE DIFFUSION OF GASES THROUGH 



52. The Same, Continued. — The preceding solution diluted with an 

 equal bulk of water showed the density p= 1.0274 a t 21 or 3.3 grams in 

 100 grams of solution, 3.4 grams in 100 grams of water, corresponding to 

 the vapor pressure 7r' = 7r(i —0.018). 



The record of results is contained in table ^^ and fig. 29 and is very pecu- 

 liar. Even apart from the usual irregularity at the beginning of the obser- 

 vation period, the curve continues to be sinuous after the weekly method of 

 observation is introduced. The mean value is probably that of pure water, 

 though the whole behavior is abnormal. The mean diffusion rates are 



?' = o.O25 c.c./day or io 10 k = o.946 



a value even in excess of the usual air value. If the final rate were taken 

 the diffusion constants would be 



r = o.oi97 c.c./day or io 10 /c = o.744 



which is more nearly the probable result. 



Table 33. — Air into air through CaCb solution (3.4 grams in 100 grams water). Vessel 

 C. Constants as in table 30. p u = 1.0274 at 21 . 



Date. 



Barom- 

 eter. 



I 



H 



Vq 



Date. 



Barom- 

 eter. 



t H 



Z'O 



Dec. 26. . 



77.10 





 17. 1 67.55 



6.895 



Jan. 



3- • 



73.98 





 18.2 



67-48 



6.865 



28.. 



75-50 



17.0 



67-55 



6.898 





10. . 



77-35 



17.7 



66.05 



6.729 



30.. 



75-74 



17-3 



67.58 



6.895 





17.. 



76.54 



17.2 



63 53 



6.483 



31.. 



76.34 



17.7 



67-55 



6.882 





24. . 



76. 10 



17.8 



62.01 



6317 



Jan. 1 . . 



76.01 



'7 9 



67.50 



6.874 





31.. 



76.17 



17.9 



60.89 



6.201 



2 . . 



76.87 



18.0 



67-34 



6.855 















W 



— 

















6-fi 



















64 



f 

















6* 



f~° 

















SfC 26 St Jan5 10 5 ZO tS 3i~ 



Fig. 29. — Chart showing loss of standard volumes 

 of gas in diver in lapse of days. Diffusion 

 of air through CaCl 2 solution. 



53. Diffusion of Air into Air Through BaCl, Solution. — The present 

 results are to be compared in series with the calcic and strontic chlorides. 

 The concentrated solution of BaCl 2 showed a density of p u .— 1.170 at 20 C, 

 therefore equivalent to 17 grams of EaCb in 100 grams of solution or 

 20.5 grams in 100 grams of water. The vapor pressure was taken as t' = it 

 (1 —0.050). The results obtained are recorded in table 34 and fig. 30 a. 



A line drawn through the observations gives the rates 



i' = 0.0077 c.c. day or io 10 /c = 0.192 

 low values, in keeping with the concentrated solution. 



