353 



This table shows that the quantity of CO.^ decreases 

 considerably Avith the rising temperature (or, in other words, 

 if the quantity had been kept constant the tension would have 

 risen) and that the quantity of carbonic acid relative to the 

 alkalinity — the saturation — increases with the dilution. These 

 important facts are rendered intelligible by looking at the whole 

 process from the point of view of chemical mass-action, set 

 forth by Goldberg & Waage. 



If two substances, Ä and B, can give rise by their mutual 

 reaction to two other substances, A^ and ß^, then, if definite 

 quantities of A and В are mingled, a mixture of all four sub- 

 stances, A, ^1, В and ß,, will result. In the state of equili- 

 brium the numbers of molecules of A is dependent on the 

 numbers of the other molecules, and these cannot be augmented 

 or diminished unless the number of Л -molecules increases or 

 decreases accordingly. 



In the case of seawater we have the surplus base and the 

 carbonic acid in definite quantities, and hence a mixture must 

 always be present of 



a h с d 



free base normal carbonate bicarbonate free, dissolved 



carbonic acid. 



Hamberg has re-tabulated his experiments in accordance 



with this view, calculating the quantity d from the percentage 



of CC2 in the current of air and the physical coefficient of 



absorption M , and disregarding a which he considered to be 



insignificant. If the alkalinity is called a and the total quantity 



of carbonic acid /9, while b and с are taken to mean, as above, 



the quantities of CO^ present as normal and bicarbonate, 



respectively, we must have: 



b = 2a — [ß — d] and 



c^ß — {d + b] 



' The coefficients of absorption for carbonic acid in seawater were not 

 experimentally determined, but Hamüeki; deduced them from Setchenows 

 experiments on solutions of pure chloride of sodium. 

 XXVI, 23 



