so ROYAL SOCIETY OF CANADA 



chromic acids and iodides. The rate is very closely proportional to 

 the concentration of the bichromate, and to the square of that of the 

 acid; the effect of the iodide can be expressed by a formula of the 

 form dx/dt = mC -{- nC^. The temperature coefficient of the rate is 

 much lower than that of any other reaction yet studied. The paper 

 has appeared in the April number of the Jour. Phys. Chem. 



5. The Rate of the formation of lodates in alkaline solutions of 

 Iodine: — Mr. E. Forster. This reaction has already been studied by 

 Schilow (Zeit. phys. Chem., 16) who, however, completely overlooked 

 the action of the potassium iodide on the rate. In colourless solutions 

 (excess of potash) the rate is proportional to the concentration of the 

 potassium iodide, to the square of the amount of iodine added, and 

 to the reciprocal of the concentration of the potash. In brown solu- 

 tions (for which a special method of analysis had to be devised) the 

 rate increases with increase in the concentration of the potash and is 

 retarded by potassium iodide. These facts point to the participation 

 of hypoiodous acid in the reaction. The experiments are not yet com- 

 pleted. 



6. The " melting " of Sodium Acetate: — Mr. Green. The crystals 

 deposited from melted sodium acetate trihydrate were analyzed and 

 found to consist of the anhydrous salt. The results of earlier analyses, 

 (Zettnow, 1866), which led to the crystals in question being considered 

 Jas a lower hydrate, must be ascribed to the difficulty of separating 

 them from the supersaturated solution without bringing about deposi- 

 tion of the trihydrate. The solubility curves of the trihydrate and 

 jof the anhydrous salt have also been determined. The so-called " melt- 

 ing point " is the temperature at which the two curves cross. 



7. An acid Ferrous Sulphate: — Mr. R. E. H ore. Experiments 

 carried out under the direction of Dr. F. B. Kenrick. 



8. The Rate of Migration of the Ions in solutions of Acetic Acid: — 

 Mr. J. W. McBain. One of the earliest triumphs of the van 't Hoff- 

 'Arrhenius theory of solutions consisted in calculating the effect of 

 dilution on the conductivity of acetic acid. The calculation in ques- 



+ - 



tion assumes that the ions in the solutions are H and CJI^Oo, and 

 their rates of migration (obtained from determinations of the conduc- 

 tivity of hydrochloric acid and of sodium acetate) are made the basis 

 of the computation. Mr. McBain's measurements of the transference 



