. Carnegie Institution of Washington publication. 196 WORK OF P. B. DAVIS. â 100 3 -e c c o â C 'S a. than that of the solvent. Even at 75°, rubidium chloride, which increases the fluidity the least, shows a positive fluidity coefficient of per cent for the N/10 solution. A table of per cent temperature coefficients of fluidity is given with each table of viscosities. These are seen to be almost equal to the temperature coefficients of conductivity, but in every case are somewhat larger. This is to be accounted for by the decrease in association of the solvent with rise in temperature, ca
. Carnegie Institution of Washington publication. 196 WORK OF P. B. DAVIS. â 100 3 -e c c o â C 'S a. than that of the solvent. Even at 75°, rubidium chloride, which increases the fluidity the least, shows a positive fluidity coefficient of per cent for the N/10 solution. A table of per cent temperature coefficients of fluidity is given with each table of viscosities. These are seen to be almost equal to the temperature coefficients of conductivity, but in every case are somewhat larger. This is to be accounted for by the decrease in association of the solvent with rise in temperature, causing a decrease in the ionization of the solute and therefore a smaller conductivity. This would in part offset the increase in conductivity due to an increase in the velocity of the ions, because of the decrease in the viscosity of the solvent with rise in temperature. The greatest viscosity lowering or increase in fluidity is to be observed in the case of the normal solution. This is obvious, since the effect is proportional to the concen- tration. The dilution curve does not pass through a minimum, but becomes asymptotic to that of the solvent at dilutions beyond the N/50. The percentage increase in fluidity becomes less also with rise in temperature, which may be accounted for by the change in the molec- ular aggregates of the sol- vent and by the greater effect of temperature than of the dissolved salt on the viscosity of the solvent. With the above facts in view, it is possible to ex- plain the minima found at low temperatures in the conductivity curves for the concentrated solutions. These minima are more marked at 25°, and in the case of those salts which give the greatest lowering of the viscosity of glycerol, viz, ammonium and rubidium iodides. In the concen- trated solution (N-N/4) the ionization is nearly constant, while the negative vis- cosity effect decreases with increased dilution. Reference to fig. 84 will show that the conductivity and fluidity curves
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