. Carnegie Institution of Washington publication. 194 WORK OF P. B. DAVIS. change in temperature would produce the greatest effect where the solvation was greatest, viz, in the more dilute solutions, and in solutions of those salts which have the greatest power of solvation. The per cent temperature coefficients are seen to be very large, being from 10 to 11 per cent between 25° and 35°. They decrease rapidly with rise in temperature, the values between 65° and 75° lying between and 5 per cent. This may be partially accounted for b}r the enormous decrease in the viscosity of glycerol with
. Carnegie Institution of Washington publication. 194 WORK OF P. B. DAVIS. change in temperature would produce the greatest effect where the solvation was greatest, viz, in the more dilute solutions, and in solutions of those salts which have the greatest power of solvation. The per cent temperature coefficients are seen to be very large, being from 10 to 11 per cent between 25° and 35°. They decrease rapidly with rise in temperature, the values between 65° and 75° lying between and 5 per cent. This may be partially accounted for b}r the enormous decrease in the viscosity of glycerol with rise in temperature. At 25° glycerol has a viscosity approximately 660 times that of water, while at 35° the value is 370 times that of water—but little more than half as great. At 75° the ratio falls to 70. In no other common solvent are the temperature coefficients of conductivity so great, and the above ratios will show to some extent why this should be the case. Tables 131 to 138, inclusive, contain the molecular conductivities at 25°, 35°, and 45° of ammonium iodide and rubidium bromide in mixtures of glycerol with water. Figs. 81 and 82 express these results graphically. The solvents were prepared by diluting n of glycerol to 1 liter and denoting the resulting solvent as a mixture of n per cent glycerol with water. It will be seen that the conduc- tivity curves of such mixtures show a decided sagging, the con- ductivity values being always less than would be expected from the law of averages. The expla- nation of this has been given by Jones and Lindsay1 and by Jones and Murray2 for mixtures of water with the alcohols, and has been extended to mixtures con- taining glycerol by Guy and Jones. When two highly asso- ciated liquids are mixed, or, to take a specific instance, when glycerol is mixed with water, it has been shown that in such a I, - V=io II, - V=50 III, — V=400 IV, - V=1600 •100. 150 III o 3 -O c o 'a "3 j> 5 S -50 Fig, Per cent. Gly
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