106 ON THE CALCULATION OF THE CONDUCTIVITY OF 
mixture, the above equations express the conditions which must 
be fulfilled that there may be equilibrium between the dissociated 
and undissociated portions of each electrolyte, both in the part 
of the mixture occupied by it and throughout the whole volume 
of the mixture. The result: 
m aN, na, N 
Vy Vo 
states that in a mixture of solutions of two electrolytes which 
have a common ion, and are in a state of equilibrium, the con- 
centration of the ions of the respective electrolytes per unit 
volume of the portions of the mixture occupied by them, must 
be the same. 
With the aid of this result we can find the ionisation co-effi- 
cients of the constituents of mixtures such as Bender 
examined. For if v’,; and v’, are the volumes of the constituent 
solutions before mixing, and ,, n, the numbers of gramme- 
molecules per unit of volume which they contain, it gives us the 
equation : 
/ / 
ay Ny 1) ap Ng V 
at = SF waareco tl) 
Vy Vo 
We have also 
Cpa Ue OPC Ma Nasir (2) 
and as the co-efficients of ionisation are functions of the 
dilution only, at constant temperature, we have 
8 
bo 
SS 
a 
~ 
> 
bo 
= 
a5 || 
to 
== 
— 
fT 
wm 
, 
Of the quantities involved in these equations, n,, 2,, Vy V, 
are known, and p may be determined by density measurements 
before and after mixture. The form of the functions in (3) and 
(4) may be determined if measurements of the conductivities of 
sufficiently extended series of simple solutions of the constituent. 
electrolytes are made. We have thus four equations with but 
four unknown quantities. 
