[ 19^ ] 



No. 22. 



IRREGULARITIES IN THE RATE OP SOLUTION OP OXYGEN 



BY WATER. 



By H. G. BECKER, A.R.C.Sc.I, AJ.C, 

 Demonstrator in Chemistry in the College of Science, Dublin ; 



AND 



E. P. PEARSON, A.R.C.Sc.I., 

 Research Student. 



(Eead March 27. Printed June 19, 1923.) 



In the course of some previous work one of the authors noticed that when 

 experiments on the absorption of gases by water were made by exposing columns 

 of air-free water to the atmosphere and then analysing the gas-content of these 

 columns after different periods of time, various small irregTilarities appeared in 

 the results, which were greater than the experimental errors involved. The 

 effect in-dicated seemed to show that instead of the process of absorption of the 

 air by the water being steady and uniform, as it is when the water is gently 

 mixed, it varied suddenly at different times, especially towards the saturation 

 point. 



This effect, though too small to be of importance on the large scale, was 

 considered worth investigating further, with a view to elucidating the process 

 by which a soluble gas is absorbed and distributed in a liquid. To do this it 

 was necessary to use a method which allowed of observing the amount of gas 

 absorbed by the liquid at any time during the whole course of the aeration. 

 At the same time it was thought desirable to eliminate temperature variation, 

 and also the variation in the humidity of the gas in contact with the liquid, so 

 that the absorption of the gas would take place under conditions which were as 

 constant as possible, and anj- effect due to these causes would be excluded. 



The apparatus shown in fig. 1 was designed for the purpose. It consists of 

 two glass bulbs, Vi and Vo, about 30 mm. diameter, and of a capacity of 60 and 

 200 e.c. respectively. The bulb Vi is provided with a capiUaiy tap (A), and is 

 fused on to one encl of the water-manometer M. The other end of the manometer 

 is fused to a four-waj^ piece on the top of the bulb Va. The remaining two 

 branches of the four-way piece are fused to a capillary and tap (H) and a gas- 

 reservoir R. The amount of gas absorbed at any time was shown by the reading 

 of the manometer, and this could be' re-set to zero at any stage of the process by 

 allowing mercury to flow into the reservoir to replace the gas which had been 

 absorbed. The whole apparatus was enclosed in a water-jacket 2" in diameter, 

 through which a stream of water from a thermostat, kept constant to a tenth of 

 a degree, was circulated by means of a pump. 



SOIENT. PROC. R.D.S., VOL. XVII, NO. 22. 2 N 



