WORK OF BASSETT. 



EXPERIMENTAL WORK. 



This investigation was undertaken for the purpose of determining what 

 effect mixtures of methyl alcohol and water would have on the relative 

 velocities of the ions of such a salt as silver nitrate. 



The work of Jones and Lindsay 1 on the conductivity of certain salts in 

 water, methyl, ethyl, and propyl alcohols, and mixtures of these solvents, sug- 

 gested this work. 



In their work, Jones and Lindsay found that the conductivities of such 

 salts as potassium iodide, ammonium bromide, strontium iodide, etc., were 

 less in mixtures of the solvents than in either of the solvents alone. Especially 

 was this the case in mixtures of methyl alcohol and water. Considering these 

 facts, the first thing to determine was whether silver nitrate would give 

 similar conductivity results, and if so, whether there was any relation between 

 this phenomenon and the relative velocities. The conductivities of silver 

 nitrate in these solvents and varying mixtures of them were determined. 

 The water and methyl and ethyl alcohols were purified by the methods de- 

 scribed by Jones and Lindsay. In each case a mother-solution was made in the 

 solvent in question, and the remaining solutions were obtained by successive 

 dilutions with some of the solvent of the same composition. In this way an 

 error was avoided which would result from the contraction when alcohol and 

 water were mixed, and also prevent the accompanying heat effect. In some 

 cases, as in very dilute solutions, where such small quantities of the mother- 

 solution were required, a second mother-solution was made from the first, 

 and the more dilute solutions made from it in the way described. The strength 

 of these mother-solutions was determined by titrating with a standard solution 

 of ammonium sulphocyanate. 



CONDUCTIVITY APPARATUS EMPLOYED. 



The apparatus described and used was similar to that employed by Jones 

 and Lindsay. The cells differed from the ordinary Arrhenius cell, being pro- 

 vided with a ground-glass top to prevent evaporation of the more volatile 

 solvents, and also to protect the anhydrous alcoholic solutions from the 

 moisture of the baths and air. The glass tubes carrying the electrodes were 

 passed through thin rubber tubes in the cap. Sealing-wax was then run over 

 the outside of the joint. 



'Amer. Chem. Journ., 28, 329 (1902). 



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