In the course of a general study of the physico-chemical effects of radiation on different compounds of nitrogen in aqueous solution, we were interested particularly in the behaviour of hydroxylamine and in the properties of the radical NH 2, the existence of which appears to be well established. It was possible to determine exactly the stages of the oxidation-reduction mechanisms from hydroxylamine to ammonia (reduction of NH 2OH) and from hydroxylamine to nitrogen and various oxides (oxidation of NH 2OH) by deeper study of the effects of high-energy radiation on aqueous solutions. One of us has published these results in entirety elsewhere, but it is interesting to note here that this study provides a means of elucidating the mechanism of certain chemical processes and, in particular, of obtaining completely original information about the effect of the radical NH 2 on the dissociation of NH 3 + ⇌ NH 2 + H +. In addition we have calculated the complete kinetics of the decomposition of hydroxylamine under radiation.