194 LIQUID HYDROGEN SULPHIDE AS AN IONIZING MEDIUM 



in a similar manner to all other organic substances which have 

 been found to give conducting solutions in hydrogen sulphide. 



Iodine in liquid hydrogen sulphide behaves exactly as an 

 electrolyte in aqueous solutions, as its conductivity increases 

 with increasing dilution and apparently tends towards a maxi- 

 mum value. In their paper on conductivities in liquid hydrogen 

 sulphide, Quam and Wilkinson state that they investigated the 

 conductivity of iodine in that solvent and reach the conclusion 

 that the current is carried by positive and negative ions of 

 iodine. In support of this they state that they made a trans- 

 port experiment on a solution of iodine and obtained no evi- 

 dence of a change in concentration at either electrode. They 

 therefore hold to the opinion expressed by Walden that the 

 iodine is dissociated into positive and negative ions and ap- 

 parently does not form a compound with the solvent. An at- 

 tempt was made to find evidences of compound formation or 

 chemical reaction. A strong solution of iodine in liquid hy- 

 drogen sulphide was prepared and the hydrogen sulphide dis- 

 tilled off into water. No traces of hydrogen iodide could be 

 found in the resulting solution and the iodine was left in the 

 tube as a mass of small crystals. Apparently iodine does not 

 react with liquid hydrogen sulphide, nor does its solution de- 

 posit compounds on cooling. Iodine is the only one of the halo- 

 gens which shows appreciable conduction in hydrogen 

 sulphide, and there seems to be no good reason why a liquid 

 having a low di-electric constant should be able to cause disso- 

 ciation. Mention may be made here of the fact that bromine 

 and chlorine show affinity for ether, alcohol, etc., at low tem- 

 peratures and form compounds; iodine does not. 



The investigation of the conductivity of antimony chloride 

 yielded a most interesting result. As this substances is an 

 inorganic salt it might be expected that its conductivity curve 

 would have the form common to all electrolytes in aqueous 

 solutions. It was found however that the curve has the oppo- 

 site forms. It would therefore be suspected that the antimony 

 trichloride formed a complex compound with the hydrogen 

 sulphide. Quam and Wilkinson investigated this reaction by 



