34 IONIZATION COEFFICIENTS OF CERTAIN 



addition, in order to determine how closely the depression in the 

 case of simple solutions can be calculated by means of ionization 

 coefficients determined by conductivity measurements, I observed 

 the depression in the case of simple solutions also. 



The work involved in making the desired test therefore 

 included the following: (1) The purification or testing of 

 the materials ; (2) the preparation and analysis of series of 

 simple solutions and the preparation of the mixtures; (3) the 

 measurement of the conductivity of series of simple solutions 

 at C. ; (4) the determination of the equivalent conductivity 

 at C. of the two electrolytes at infinite dilution; (5) the 

 calculation of the ionization coefficients of the simple solutions ; 

 (6) the measurement of the depression of the freezing-point for 

 the simple solutions ; (7) the calculation of the depression for 

 the simple solutions by means of the ionization coefficients 

 obtained from the conductivity measurements ; (8) the measure- 

 ment of the depression of the freezing-point in the case of the 

 mixtures; (9) the determination of the ionization coefficients of 

 the electrolytes in the mixtures, and (10) the calculation of the 

 depression of the freezing-point of the mixtures by means of 

 these coefficients. 



The Materials, 



The salts were obtained as chemically pure from Eimer and 

 Amend of New York, and were re-crystallized carefully three 

 times, after which treatment no appreciable impurities could be 

 detected. 



he water used was purified by Hulett's* method, except 

 that a block tin condenser was employed instead of a platinum 

 one. Portions of the distillate were treated in the same manner 

 as to exposure to air, etc., as a solution would be, and their 

 conductivity measured. It was found to vary from 0.88 X 10~ 10 

 to 0.96 X 10~ 10 , expressed in terms of the conductivity of mer- 

 cury at C. It was kept in bottles which had been used for 

 this purpose for several years. 



*Journ. Phys. Chem. 1, 91, (1896). 



