Chemical Forms Assumed by C14 Produced by Neutron Irradiation of Nitrogenous Substances

Abstract

The nature of the radioactive compounds formed in the production of C¹⁴ by neutron irradiation of nitrogen‐containing material of various types has been investigated. Of the radioactive compounds sought, carbon dioxide and carbon monoxide were found in all samples which contained oxygen, either in the parent compound or in the solvent water. Formic acid and methanol were found only in water solutions. Hydrogen cyanide, on the other hand, was found in no solution, but was found in all the pure substance samples except ammonium nitrate and aniline. Methane was found only in those hydrogenous substances containing no oxygen. Formaldehyde was never found. An attempt is made to interpret the results in terms of the processes in which the C¹⁴ atoms must be involved in the dissipation of the recoil energy associated with their formation. The fact that several compounds are produced in radioactive form in the original irradiation eliminates the necessity for the synthesis from radioactive carbon dioxide of these compounds for use in tracer work. A simplified method for the preparation of C¹⁴ is suggested.