﻿Constitution of Aqueous Solutions. 19 



If we exclude the exceptional ratio for K 2 S0 4 , the mean 

 value of the ratio of rk 2 in the surface to r in the bulk is 1*9, 

 with a range from 1 to 3. Experimental uncertainty affects 

 the value of the ratio much. The main result, however, is 

 clear, that dissociation produced by the solute in the surface 

 layer is the cause of the exceptional behaviour of the surface 

 tension of solutions. If we can assume that an equivalent of 

 solute dissociates as many molecules of (H 2 0) 3 in the surface 

 as in the bulk, then P = 1'9 and £=-l'4 ; that is to say, that 

 on the average the concentration of a salt solution is 1 *4 times 

 as great in the surface film as in the bulk. The values of a 4 

 obtainable from (24) have no direct bearing on the present 

 subject. They have been already considered in the paper 

 cited. All the other properties of solutions, such as refraction 

 and viscosity, can be treated in the same way as those selected 

 for discussion in this paper. 



6. Summary. 



The contraction occurring when electrolytes dissolve in 

 water is due to their changing some of the trihydrol of the 

 water into dihydrol. The number t of gramme molecules of 

 (H 2 0) 3 changed into (H 2 0,) 2 by a gramme equivalent of 

 solute is the algebraic sum of parts t due to the positive and 

 negative ions. For positive ions t is positive, and for 

 negative negative ; that is to say, a positive ion changes 

 (H 2 0) 3 into (H 2 0) 2 , and a negative changes (H 2 0) 2 into 

 (H 2 0) 3 . This supplies a strong confirmation of the theory of 

 the ionic dissociation of dissolved electrolytes. It indicates 

 that the energy relations of positive and negative electricity 

 to the surrounding dielectric are different; a fact to be taken 

 account of in a complete theory of electricity. 



If \ is ionic velocity, K dielectric capacity of the stuff 

 of an atom, and B the limiting volume of the gramme atom, 

 then for positive ions t/(\KB ¥ )3 is constant, and for negative 

 t/(\KB^ is constant. These formulae are obtained by a 

 theory of the electric action of ions on (H 2 0) 3 and (H 2 0) 2 

 molecules. This theory tends to confirm the existence in 

 water of what has been called a stion, an atom or a molecule 

 like H 2 with both a positive and a negative electron which 

 have not coalesced as in the H 2 of water vapour. This 

 stion is an intermediate product in the ceaseless making and 

 unmaking of (H 2 0) 3 in water, and plays an important part 

 in ionization. 



From a consideration of the special properties of the H ion 



C2 



