CHEMISTRY. 345 



Jones, Harry C, Johns Hopkins University, Baltimore, Maryland. Con- 

 tinuation of investigations on the absorption spectra of solutions and on 

 the conductivity and viscosity of electrolytes in water and non-aqueous 

 solvents. (For previous reports see Year Books Nos. 2-14.) 



A number of problems were investigated during the year.^ 



Dr. Davis, continuing his investigations on the viscosity of caesium 

 salts, studied their behavior in mixed solvents containing glycerol. 

 It had been previously shown that rubidium salts produce a phe- 

 nomenal lowering of the viscosity of glycerol and its mixtures with 

 water, the results furnishing additional confirmation of the hypothesis 

 of Jones and Veazey to account for such negative viscosity coefficients. 

 With csesium salts a still greater lowering of the viscosity of the 

 solvents used has been observed, which is to be attributed to the 

 large atomic vohmie of csesium. 



Dr. Davis, with the assistance of Mr. Johnson, has also extended 

 his studies of the conductivity and viscosity of solutions of electro- 

 lytes in formamid as a solvent. The work has necessarily progressed 

 somewhat slowly, owing to the great difficulties encountered in the puri- 

 fication of the solvent. A series of nitrates and of formates have been 

 studied. It is hoped to investigate certain representative organic acids 

 in this solvent and finally to study the behavior of solutions m mixed 

 solvents containing formamid. A fuller report on this work will appear 

 subsequently. 



Dr. Davis has also devised an efficient vacuum desiccator for use 

 in the preparation of anhydrous samples of the hydrated compounds 

 studied in non-aqueous solvents. 



Dr. Hulbert and Dr. Hutchinson, using the Littrow spectroscope 

 designed by Professor J. A. Anderson and the improved radiomi- 

 crometer built by Shaeffer and Paulus, have carried out a systematic 

 and thorough study of the absorption coefficient of solutions for 

 monochromatic radiation. They have determined the absorption 

 coefficient (a) of a number of inorganic salts in water and in several 

 of the alcohols at intervals of 20ixfx to 40/>i)u throughout the region of the 

 spectrum where the pure solvents possess appreciable absorption, 

 600)Uju to l,300)U^t for many solutions. The values of a plotted 

 against the corresponding wave-lengths form the absorption curve 

 for any given solution. For each salt a series of solutions, varying 

 in concentration from saturation to extreme dilution, was prepared 

 and the absorption curve was drawn for each solution. From the 

 data thus obtained, the molecular absorption coefficients (A) for the 

 salts in the various solvents used were calculated and plotted against 

 the gram-molecular concentrations. A careful comparative study was 

 then made of the resulting curves, 



'On account of the sudden death of Professor Jones in April 1916, several new lines of inves- 

 tigation had to be discontinued. The work reported on here was either nearly completed or 

 well under way at the time of Professor Jones's death. 



