Passage of Electricity through Liquids, 281 



Simultaneously with the temperature and concentration, the 

 quantities e and e' also undergo changes ; for Wild"^ discovered 

 that the electromotive forces between solutions of salts change 

 with the concentration of the solutions. 



With the nature of the solvent all constants of the expression 

 (24) must also change ; and it cannot be surprising that when 

 the same salt is dissolved in water it conducts better than when 

 dissolved in absolute alcohol, and this solution, again, better 

 than a solution in amylic alcohol, as Hittorff found — or when 

 ConnelJ asserts that etherial solutions do not conduct at all, and 

 alcoholic solutions conduct very badly, whilst an aqueous solution 

 of the same salt is easily decomposed by an electrical current. 



It even appears as if those constants changed with the state 

 of aggregation ; for Hittorf § observed that a dilute aqueous 

 solution of hydrochloric acid is easily decomposed by an elec- 

 trical current, whilst gaseous hydrochloric acid with the same 

 number JO of equivalents in the unit of volume does not conduct 

 the electricity of a hydrobattery. 



It may be observed that this matter would be far more diffi- 

 cult to understand if we were to assume that the constituent 

 molecules of a chemical combination continually separate them- 

 selves and again unite, and in electrochemical decomposition 

 there is merely an augmentation of the path of the free partial 

 molecules (compare § 62). 



As through the presence of another salt in a solution the con- 

 stants C, C, €, e' must be changed, the formulae show that the 

 conductivity of a mixture of salts will not stand in a simple re- 

 lation to the conductivity of the pure solution of a salt, as is in 

 fact shown by the experiments of Paalzowl|. 



§ 66. 



Equations (17) and (27) of § 55 show that the quantities of 

 separated substances on the electrodes, as well as the proportion 

 of these substances, when several chemical combinations con- 

 tained in the same liquid are decomposed simultaneously, must 

 be independent of the density of the current ; and this conclu- 

 sion is confirmed by experiment. 



The theory leads to this without presupposing Faraday^s law; 

 and all experiments which prove the latter prove at the same 

 time the above conclusion, since Faraday's law holds indepen- 

 dently of the density of the current. It is moreover this law 



* Pogg. Ann. vol. ciii. p. 384 (1858). 



t Ibid. vol. cvi. pp. 550, 552, & 553 (1859). 



% Phil. Mag. vol. xvii. p. 353 (1841). 



§ Pogg. Ann. vol. cvi. p. 585 (1859). 



II Berl.Monatsb.\86S,-p.490. 



