110 ON THE CALCULATION OF THE CONDUCTIVITY OF 
From the equations 
1 9 
Vii= ae amd eV te — 2 
1 
Uo 
it follows that 
, Moye 2 d Tae , , 
Hence f e and h g being proportional to the volumes of the 
solutions before mixing will be unequal. As before, we have 
to determine points 7 and & on curves c d and A B respectively, 
having a common abscissa O / and so situated that if p is equal 
to unity, 
kl+j l=eft+g h, 
and if p is not equal to unity, 
kl+jl=p (ef+g h). 
If, in cases in which p is equal to unity, the pointsy, k be 
properly selected, it is obvious that a line 7 m drawn through @ 
the point of bisection of e g, parallel to the axis of ionic concen- 
trations, O h, will bisect 7 k. Hence the points 7, k, will be 
easily determined by inspection. If p is not equal to unity, the 
points corresponding to 7 and & may be determined by proceeding 
in a manner similar to that used in the case of a mixture of 
equal volumes of the constituent solutions. To avoid complica- 
tion the construction is not inserted in the diagram. 
It will be obvious that the values of “1 and @ for a solution 
containing two electrolytes with a common ion, may be 
determined in the above way, whether it has been formed by the 
mixing of two simple solutions or not. It may always be 
imagined to have been formed in this way, and in cases in which 
p is not negligible, if data are not available for its determination, 
special density measurements may be made. 
DaTa FOR THE CALCULATIONS. 
Bender's paper contains all the data required for the calcula- 
tion of the conductivities of mixtures of solutions of potassium 
and sodium chlorides, with the single exception of the specific 
