From the Introduction.
We have endeavored for some time to secure enough caesium salts to study their viscosities in pure and in mixed solvents, but only within the past year have we been successful. Through the courtesy and cooperation of Professor James Lewis Howe of Washington and Lee University, a quantity of caesium sulphate was placed at our disposal. This was converted first into the hydroxide, then into the carbonate, and finally into the chloride and nitrate; and with these salts this investigation has been carried out.
Caesium is the most electro-positive of all the elements, and is further distinguished by possessing the largest atomic volume, being followed in this respect by rubidium and potassium, respectively. Since salts of the latter two elements are of great interest from the viscosity standpoint, it would be expected that caesium salts would possess, to a much more pronounced degree, any peculiarities shown by salts of rubidium and potassium.
An examination of the literature bearing on viscosity shows that, in general, only the salts of the three metals mentioned above are known to lower the viscosity of water. The effect of potassium and rubidium salts on the viscosities of solvents other than water, and of mixtures of such solvents with one another and with water, has been the subject of ear her investigations in this laboratory; and this series of investigations can now be regarded as partially completed by this study of csesium salts in these solvents. The present investigation, therefore, has been made to comprise a study of the viscosities of the two caesium salts, chloride and nitrate, in water and in binary mixtures of methyl alcohol, ethyl alcohol, and acetone with water.
The results obtained with these salts of caesium in formamid as a solvent are published in Chapter II, and further determinations of their behavior in glycerol and glycerol-water mixtures, as well as in mixed solvents containing formamid instead of water are now in progress.
