Radiochemical dating definition chemistry
radioactivity,spontaneous disintegration or decay of the nucleus of an atom by emission of particles, usually accompanied by electromagnetic radiation. of California and was a chemist (1941–45) in the war research division at Columbia......The energy produced by radioactivity has important military and industrial applications...... the branch of chemistry concerned with the chemistry of radioisotopes, elements, and substances, the laws governing the physicochemical behavior of this radioactive matter, the chemistry of nuclear transformations, and the physicochemical processes that accompany these transformations.Radioisotopes are also obtained artificially by irradiating various substances with nuclear particles. In many cases, hundreds, tens, or even just a few atoms of radioisotopes are present in many other atoms.(Only in the production of nuclear fuel is Pu obtained in significant quantities, though even here its concentration upon irradiation of U with neutrons is low.) It is therefore possible to separate radioactive elements and isotopes only from extremely dilute systems, and their weights in most cases cannot be determined.Also studied are the properties of radioactive substances and the transformations of these substances under the effect of their own radiation.The chemistry of radioactive elements is the chemistry of the natural radioactive elements from Po to U (atomic numbers 84–92) and of the artificial elements Tc (atomic number 43), Pm (atomic number 61), Np (atomic number 94), and all subsequent elements up to atomic number 106.For example, by feeding plants carbon dioxide that contains the radioisotope carbon-14 and by monitoring the carbon compounds through the plants' life cycle, the intermediate stages of the photosynthetic process can be determined. Most natural radioisotopes are daughter isotopes, that is, products of the decay of Th.The concentrations of some of these isotopes in the equiponderant ores U and Th per 1 gram of pure parent isotope are presented in Table 1 on page 421.
The chemistry of new atomlike species—positronium, muonium, and mesic atoms—has also been established. The physicochemical behavior of extremely dilute solutions is very complex.This behavior may be described by the laws of ideal solutions, though sometimes these laws are not obeyed because of secondary processes related to, for example, adsorption or radiolysis.By using especially sensitive methods for monitoring radioactive decay, it is possible to detect the presence of single atoms of a radioisotope and to establish the fact of their decay.The development of radiochemistry into an independent branch of chemistry began at the end of the 19th century with the work of M. Curie, who in 1898 discovered and isolated Ra and Po.
By convention, the chemistry and technology of nuclear fuel is included in this subdivision.