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Francium-223 is the most stable isotope, with a half-life of 21.8 minutes, [8] and it is highly unlikely that an isotope of francium with a longer half-life will ever be discovered or synthesized. [22] Francium-223 is a fifth product of the uranium-235 decay series as a daughter isotope of actinium-227; thorium-227 is the more common daughter. [23]
The insoluble compounds are used to extract francium from other radioactive products, such as zirconium, niobium, molybdenum, tin, and antimony, using the method mentioned in the section above. [3] The CsFr molecule is predicted to have francium at the negative end of the dipole, unlike all known heterodiatomic alkali metal molecules.
Francium, formerly known as eka-caesium and actinium K, is a chemical element that has the symbol Fr and atomic number 87. It has the lowest known electronegativity and is the second rarest naturally occurring element (after Astatine). Francium is a highly radioactive metal that decays into astatine, radium, and radon.
The real element 99, einsteinium, has no such qualities. Element 115 Ufology, various works Widely known within the sci-fi and UFO community; since, according to ufologist Bob Lazar, it is used by alien engines to generate anti-gravity and propulsion. The real element 115 is moscovium, a synthetic element with an extremely short half-life ...
I don't know for sure what else was present in the mixture.) Besides the practical use in separating francium from other elements, the fact that it coprecipitated with caesium was part of the evidence that francium was an alkali metal. --Itub 12:36, 11 April 2007 (UTC) Cool. Your example seems better than mine. That makes a lot more sense.
This is a list of radioactive nuclides (sometimes also called isotopes), ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds.
Perey named the element francium, after her home country, and it joined the other alkali metals in Group 1 of the periodic table of elements. [3] [7] Francium is the second rarest element (after astatine) — only about 550g exists in the entire Earth's crust at any given time — and it was the last element to be discovered in nature.
Francium (87 Fr) has no stable isotopes, thus a standard atomic weight cannot be given. Its most stable isotope is 223 Fr with a half-life of 22 minutes, occurring in trace quantities in nature as an intermediate decay product of 235 U. Of elements whose most stable isotopes have been identified with certainty, francium is the most unstable.