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Although rubidium is monoisotopic, rubidium in the Earth's crust is composed of two isotopes: the stable 85 Rb (72.2%) and the radioactive 87 Rb (27.8%). [23] Natural rubidium is radioactive, with specific activity of about 670 Bq/g, enough to significantly expose a photographic film in 110 days.
The propensity for any two substances to form a solid solution is a complicated matter involving the chemical, crystallographic, and quantum properties of the substances in question. Substitutional solid solutions, in accordance with the Hume-Rothery rules, may form if the solute and solvent have: Similar atomic radii (15% or less difference)
Radiochemistry is the chemistry of radioactive materials, where radioactive isotopes of elements are used to study the properties and chemical reactions of non-radioactive isotopes (often within radiochemistry the absence of radioactivity leads to a substance being described as being inactive as the isotopes are stable).
Similarly, using other radioactive elements, the age of rocks and other geological features (even some man-made objects) can be determined; this is called Radiometric dating. Environmental scientists use radioactive atoms, known as tracer atoms, to identify the pathways taken by pollutants through the environment.
Krypton-85, with a half-life 10.76 years, is formed by the fission process with a fission yield of about 0.3%. Only 20% of the fission products of mass 85 become 85 Kr itself; the rest passes through a short-lived nuclear isomer and then to stable 85 Rb. If irradiated reactor fuel is reprocessed, this radioactive krypton may be released into ...
The production methods for different isotopes vary, and only those for promethium-147 are given because it is the only isotope with industrial applications. Promethium-147 is produced in large quantities (compared to other isotopes) by bombarding uranium-235 with thermal neutrons. The output is relatively high, at 2.6% of the total product. [56]
Two radioactive, cosmogenic isotopes are the byproduct of cosmic ray spallation: 22 Na has a half-life of 2.6 years and 24 Na, a half-life of 15 hours; all other isotopes have a half-life of less than one minute. [17] Two nuclear isomers have been discovered, the longer-lived one being 24m Na with a half-life
The gas mixture extracted from the solutions contains H 2, O 2, He, Rn, CO 2, H 2 O and hydrocarbons. The mixture is purified by passing it over copper at 993 K (720 °C; 1,328 °F) to remove the H 2 and the O 2, and then KOH and P 2 O 5 are used to remove the acids and moisture by sorption.