150 



WORK OF M. R. SCHMIDT. 



of the three. Relations exactly analogous to these have been pointed out by Jones and 

 Veazey, and the mechanism of the effect has been sufficiently discussed in the first 

 part of this work. 



The viscosity of pure glycerol at 25 (or 6.330) is 1,120 times that of methyl 

 alcohol at the same temperature. A wide range of viscosity has thus been covered, 

 yet the same relations hold that obtain in mixtures of the much more fluid solvents 

 studied by Jones and his coworkers. The fluidities at 25 are plotted as curves in 

 fig. 69. Curve I represents the fluidities of glycerol-methyl alcohol mixtures, curve 

 II represents glycerol-water, and curve III represents glycerol-ethyl alcohol. The 

 curves resemble the conductivity curves very closely, show the same sagging and 

 have no minima. 



Table 113. Viscosity and Fluidity of Solutions in Mixtures of Glycerol and Methyl Alcohol 



at 25 and 35. 



Table 114. Viscosity and Fluidity of Solutions in Glycerol at 25 and 35. 



The temperature coefficient of fluidity of pure glycerol between 25 and 35 

 is 11.53 per cent, and this is very nearly equal to the temperature coefficients of 

 conductivity of the salts used in this work. In all the solutions the temperature 

 coefficient of fluidity is greater than the temperature coefficients of conductivity, 

 as has been hitherto observed in practically all cases. This is probably due partly 

 to the decrease in dissociation with rising temperature. 



It will be seen that in the majority of cases the temperature coefficient of fluidity 

 of any solution is slightly greater than that of the solvent. As is known, dissociation 

 decreases slightly with rising temperature. This would cause the solution at higher 

 temperature to contain a greater number of whole molecules, whose volume would 

 be equal to that of their component ions, but whose frictional surfaces would be less. 

 This would decrease the total frictional surface of the particles in the solution and 

 an increase in the fluidity would result, in addition to that caused by the ordinary 



