Development of the radiation chemistry of aqueous solutions

Abstract

Aqueous radiation chemistry began when dissolved radium salts were found to decompose water. Later it was found that chemical reactions took place in water and aqueous solutions irradiated only by 3-and y-rays of radium. From these modest beginnings, the current prominence of this branch of chemistry has gradually developed. Three periods are: 1900-25, 1925-40, and 1940 to the present. Except for some basic observations little progress was made in the first quarter century. Consequently we shall deal only briefly with this era. But because many basic principles were established in the sometimes overlooked second era, we shall discuss this period at some length; and then because we are familiar with prodigious post-war developments, we shall treat these only lightly.Early Period Radium salts and radon decompose aqueous solutions liberating hydrogen, oxygen, and hydrogen peroxide. These effects were described by Geisel (1) in 1902 and were later studied by Cameron and Ramsey (£), Debierne (3), Kernbaum (4), LTsher (3), and Duane and Scheuer (3). The decomposition of water into hydrogen and oxygen was regarded as an electrolysis because it was known that an ionized gas conducts an electric current and that an electric current passing through a solution liberates hydrogen and oxygen at the electrodes. These radiation effects are due principally to the release of a-particles from the radium.Presented as part of (Lie Lind Jubilee Symposium on Development of Radiation Chemistry, sponsored jointly by the Divisions of Chemical Education and Physical Chemistry at tLie 135th

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