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UNIVERSITY OF VIRGINIA PUBLICATIONS 



Densities and viscosities of solutions of lithium chloride and sodium chloride. 

 (For comparison with potassium iodide.) 



* Van Nostrand's Chemical Annual. (1913.) 



t Landolt & Bomstein (4 Auflage.) 



tt Landolt & Bornstein (4 Auflage), page 273. 



§ Wagner, Zeit ftir Phys. Chemie, v, 31. 



(Transformed from per cent to normal data by the writer.) 



Determination of viscosity and density of KI solutions. . 



The apparatus used in determining the density consisted of a very 

 accurate set of hydrometers, graduated to three decimal places and readily 

 estimated to the fourth place. The viscosity determinations were made 

 with the usual Ostwald-Poiseulle apparatus. The one used for the first 

 nine values was a commercial viscosity meter having a very short period 

 of delivery (about 45 seconds at 25°). The last four determinations were 

 made with a home made viscosity meter made by Dr. Edgar; which had a 

 period of about 100 seconds. For our purposes the results found by using 

 either apparatus are sufficiently accurate. 



The formula used to obtain the relative viscosity is: z/zi = t/ti (30, 31). 

 In table VII z at 25° for water is taken to be unity, the viscosity at 

 , 25° is taken to be 0.50 of that at zero, and the viscosity of water at zero 

 is taken to be 0.018086 C.G.S. units (32) (33). For our unmediate pur- 

 pose the unit chosen is of no importance, yet in view of the fact that no 

 satisfactory table of viscosities for potassium iodide solutions is known, 

 it seemed worth while to give these values in terms of all commonly used 

 units. The best data that could be found on this subject was that of 



