radon-219

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radon-219

chemical isotope

Also known as: An, actinon

Learn about this topic in these articles:

discovery and characteristics

In radon
Radon-219 (actinon; 3.92-second half-life), which is associated with actinium, was found independently in 1904 by German chemist Friedrich O. Giesel and French physicist André-Louis Debierne. Radioactive isotopes having masses ranging from 204 through 224 have been identified, the longest-lived of these being radon-222, which has…
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