(1) Kettenreaktionen (2) The Kinetics of Chemical Change in Gaseous Systems

Abstract

THE theory of chain reactions was introduced in order to account for the abnormally large yields which are often found in photochemical reactions, when compared with Einstein's ‘Law of Photochemical Equivalence’, according to which each quantum of absorbed light activates or decomposes one molecule of the absorbing medium. Thus Bodenstein in 1913 found that, in mixtures of hydrogen and chlorine, 105 molecules were decomposed by each quantum instead of only one. In order to maintain the validity of Einstein's law, he therefore postulated that a secondary action took place, in which the primary product was regenerated again and again, so that an indefinitely large yield of the product could be obtained. For the special case of hydrogen and chlorine, Nernst in 1918 postulated the following mechanism:

(1) Kettenreaktionen.

Von Klaus Clusius. (Fortschritte der Chemie, Physik und physikalischen Chemie, herausgegeben von Prof. Dr. A. Eucken, Band 21, Heft 5.) Pp. iv + 73. (Berlin: Gebrüder Borntraeger, 1932.) 12.80 gold marks.

(2) The Kinetics of Chemical Change in Gaseous Systems.

By C. N. Hinshelwood. Third edition. Pp. vii + 392. (Oxford: Clarendon Press; London: Oxford University Press, 1933.) 15s. net.