Electro-chemistry. Part I, General theory / by R.A. Lehfeldt ... Including a chapter on the relation of chemical constitution to conductivity, by T.S. Moore.

  • Lehfeldt, R. A. (Robert Alfred), 1868-1927.
Date:
1904
Catalogue details

Licence: In copyright

Credit: Electro-chemistry. Part I, General theory / by R.A. Lehfeldt ... Including a chapter on the relation of chemical constitution to conductivity, by T.S. Moore. Source: Wellcome Collection.

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    be calculated from the same observations, and it is lound that the coefficient regularly increases as the conductivity decreases, as the following table shows:— Ion. Ionic conductivity (180). Temp. coeflT. (i8°). Li 33 44 0-0265 Na 4355 0*0244 Ag S4‘02 0*0229 K 64-67 0-0217 Cs 68-2 0*0212 H 318-0 0-0153 One consequence of this is that rise of temperature tends in the direction of making the mobilities of the ions all equal, and consequently tends to make the migration ratio of all electrolytes approach the value 7. § 8. THE LAW OF DILUTION The agreement observed between the degree of dissociation of electrolytes as measured by conductivity, and by osmotic pressure measurements, is not the only argument in favour of Arrhenius’ theory. An important confirmation has been ob- tained by applying the law of mass action to electrolytes. It has already been remarked that in an electrolyte there is a constant interchange of ions : molecules are broken up, and their dissociated parts recombine in different ways; and the state of equilibrium that exists at any time is of the statistical character familiar in the theory of gases. That is, a certain average proportion of molecules are dissociated, but no par- ticular molecules are always so. The main condition governing equilibrium of this character is the law of mass action (Guldberg and Waage’s law), the mathematical consequences of which have been very fully worked out.1 AVe need at present only consider its application to the special case of chemical equilibrium known as dissociation; i.e. when a single molecule breaks up into two or more parts. ' See Mellor, “ Chemical Dynamics,” in this series.