124 ON THE VISCOSITY 
Determination of Ionization Coefficients in the Mixture. 
The method proposed by 7? Prof. MacGregor for finding the 
ionization coefficients in a mixture of two electrolytes having an 
ion in common, is by solving graphically the following equa- 
tions : 
aye, (4) 
1 2 
iN. VEE NE ea eed oes (5) 
See AC Va): ARN CNNER gtr youll) 
1 
a, if 
v= PNM ae ass aks Ai 
where the electrolytes are denoted by 1 and 2, the concentra- 
tions (in gramme-equivalents per litre) of the mixture with 
respect to them by N, and N, respectively, their ionization 
coefficients by a, and a@,, and their regional dilutions (in litres 
per gramme equivalent) by V, and V,, the regional dilutions 
being the dilutions of the electrolytes in the regions which they 
are supposed to occupy in the mixture, or the dilutions of the 
constituent isohydric solutions. 
His graphical mode of solving these equations involves the 
drawing of dilution-ionic-concentration curves, which, as they 
have great curvature for moderately dilute solutions, cannot be 
drawn with great accuracy unless a large number of observa- 
tions of the conductivity are available. As mentioned above, 
extensive series of observations of the conductivity in the case 
of the salts under consideration were available; but they were 
all made at 18° C. and required therefore to be reduced to 25° C, 
before they could be used. In order to reduce this labour as 
much as possible I devised another mode of solution which 
requires only a comparatively small number of observations. It 
is based on the fact that the specific-conductivity-concentration 
Trans. N.S. Inst. Sci., 9, 101, 1895-96; also 10, 68, 1898-99. 
