VISCOSITY MEASUREMENTS. 



193 



20- 



100 # 

 Percentage of Acetone 



FIG. 97. CONDUCTIVITY OF POTASSIUM SULPHOCYANATE IN 

 MIXTURES OF ACETONE AND ETHYL ALCOHOL AT 25. 



VISCOSITY MEASUREMENTS. 



The method used for measuring the viscosity of solutions throughout this 

 work is that employed by Ostwald. 1 The viscosities have been calculated 

 from the following formula : 



in which n is the coefficient of viscosity for water, is the specific gravity 

 of water, and to the time of flow of water through any given capillary at 

 a given temperature ; n is the viscosity coefficient of the solution investigated, 

 S is its specific gravity as compared with water as unity at any given tempera- 

 ture, and t is the time of flow of the given solution at that temperature. In the 

 following tables the values for pure water at and 25 were taken from the 



1 Ostwald-Luther : Physiko-chemische Messungen, Aufl. 2, p. 259. 



