Abstract
ON Dec. 17, 1931, the Chemical Society devoted an ordinary scientific meeting to a discussion on the critical increment of homogeneous reactions. It was immediately apparent that the material then presented and the observations then offered should be put on permanent record in an accessible form, and this has since been done by the publication of a separate pamphlet (1s. 6d.) bearing the imprint of the Society a,nd following the form of its Journal. The discussion was opened by Mr. C. N. Hinshelwood, whose subject was the energy of activation of chemical reactions. The magnitude and nature of activation energy, catalytic phenomena, and the contributions of quantum mechanics to the problem were among the matters considered. Mr. E. J. Bowen followed with a paper on photochemistry and chemical reactivity, referring to photosensitisation, the phenomenon of ‘predissociation’ discovered by Henri, and the direct reaction of excited and normal molecules. Prof. A. J. Allmand's contribution dealt with the variation of quantum efficiency with wave-length in photochemical reactions; five different types of effect are distinguished, and their incidence in affecting the quantum yield was examined. Prof. E. K. Bideal discussed transition reactions, while Dr. F. G. Soper gave an account of researches on the effect of solvents on reaction velocity. Dr. T. Iredale communicated a short contribution dealing with the heat of activation of hydrogen iodide. In the spontaneous discussion which followed, Dr. R. G. W. Norrish, Mr. C. R. Bailey, Prof. Allmand, Mr. H. W. Thompson, and Mr. Hinshelwood took part. Their observations, together with the full text of the principal contributions, are to be found in the publication already mentioned.
Article PDF
Rights and permissions
About this article
Cite this article
Chemical and Photochemical Reactivity. Nature 129, 340 (1932). https://doi.org/10.1038/129340a0
Issue Date:
DOI: https://doi.org/10.1038/129340a0