Conductivities and Viscosities in Formamid and in Mixed Solvent*. 95 



Tables 49 to 52 show the molecular conductivity and viscosity of 

 tetraethyl ammonium iodide, rubidium iodide, lithium nitrate, and 

 calcium nitrate in binary mixtures containing formamid and ethyl 

 alcohol. In table 56 a comparison is made at 25 between the con- 

 ductivities in these mixtures and in the pure solvents. 



TABLE 56. Comparison of Molecular Conductivity in Mixtures of Formamid 



and Ethyl Alcohol at 25. 



Carnegie Inst. Wash. Pub. No. 80, 84. 



n -Ibid,, 97. 



One of the most important facts brought out in this table is that 

 tetraethyl ammonium iodide, rubidium iodide, and lithium nitrate 

 show an increase in molecular conductivity up to a concentration of 

 25 per cent formamid and 75 per cent ethyl alcohol mixture. Lithium 

 nitrate was the only salt of these three whose conductivity values in 

 ethyl alcohol were available, and as these values are about of the same 

 order of magnitude as those in pure formamid, it appears that a maxi- 

 mum is reached in conductivity. This relation interpreted in terms of 

 previous work on other solvents means that there is an increase either 

 in the mobility of the ions or in the dissociation in mixtures with 75 

 per cent ethyl alcohol and 25 per cent formamid, or both. From the 

 viscosity data discussed below the first assumption seems to be the 

 most probable. 



