Passage of Electricity through Liquids. 28B 



ture of dilute sulphuric and hydrochloric acid, with varying 

 density of the current, BufF* obtained at the anode a mixture of 

 ijhlorine and oxygen of almost the same composition. 



§67. 



It follows from equation (15), § 55, that in the unit of time 

 different numbers of partial molecules are conducted through the 

 same section to the anode and to the cathode, numbers propor- 

 tional to the intensity of the current and to a constant ; this 

 latter has different values for different liquids, but for the same 

 liquid is independent of the section of the thread of liquid, or, 

 consequently, independent of the density of the current. 



This is in agreement with experiment. 



MM' 



— and — r denote the number of partial molecules which are 



ad ^ 



conducted to the cathode and anode in the unit of time respec- 

 tively. The proportion of the two magnitudes can be found 

 approximately by chemical analysis of the solution in the vicinity 

 of the electrodes before and after the current has passed, pro- 

 vided the electrolyzed salt (or acid hydrate, w^hich in this case 

 as well as heretofore may be included in the expression salt) be 

 dissolved in water or some other liquid. 



At the same time no account is taken of the solvent, although 

 upon every partial molecule of this solvent a certain quantity of 

 free electricity will be accumulated. If the force K given by 

 expression (4) (§ 52) is great enough to separate the partial 

 molecules of this solvent, then simultaneously with the dissolved 

 salt this solvent will also be decomposed ; and thus it would be 

 only in the case of both partial molecules moving with equal and 

 opposite velocity, of 



Ce being =-CV, 



that, as regards the molecules of the solvent, the concentration 

 of the liquid would remain the same in every part. If K is not 

 great enough, and the sum of the quantity of electricity accumu- 

 lated on the molecules of the solvent not equal to 0, then a move- 

 ment of the total molecules of the liquid to the anode or cathode 

 takes place, and consequently also a simultaneous change in the 



IM M' 

 difference of concentration produced by the magnitudes — and —p. 



As soon as in different places of the liquid the specific gravi- 

 ties are different, gravity and diffusion will likewise change the 

 concentration of the different portions. 



In an extensive series of solutipns of salts and hydrated acids 



* Liebig's Annalen, vol. cv. p. 156 (1858), 



