Some Recent Advances in Radiochemistry*

Abstract

IN the decade since the discovery of atomic fission by Hahn and Strassmann, the subject of radio-chemistry has undergone rapid development. It has always been in the background of all the major advances in radioactivity, and the very magnitude of these advances in recent years has resulted in the presentation to the chemist of a wide range of new problems. Three of these will be discussed briefly here. The first, the chemical separation of the fission products of uranium and other fissile elements, is largely a matter of chemical analysis and differs from more familiar analytical problems only in complexity and in the fact that microchemical techniques are used. The second problem, that of fitting the many new radioactive isotopes of the heavy elements into modifications of the classical decay series, has been solved by a combination of the physical and the chemical methods of approach. The third major problem is the study of the chemistry of the new transuranic elements neptunium, plutonium, americium and curium, as well as of those of atomic numbers 87 (francium), 85 (astatine), 61 (illinium or prometheum) and 43 (masurium or technetium), which probably have not been isolated from natural sources but are now available, in small amounts, in the form of radioactive isotopes formed by suitable nuclear transformations.