Search results
Results from the WOW.Com Content Network
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]
Name Source Notes Adamant / Adamantine : Greek mythology Adamant has long meant any impenetrably or unyieldingly hard substance and, formerly, a legendary stone or mineral of impenetrable hardness and many other properties, often identified with diamond or lodestone. [1]
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.
However, it would appear that francium perchlorate has been formed, as it coprecipitates with caesium perchlorate, and several other insoluble francium salts are similarly known (Hyde, E.K., Radiochemical Methods for the Isolation of Element 87 (Francium), J. Am. Chem. Soc., 1952, 74, 4181) The article also quotes a value for the Pauling ...
When you buy a bottle of vitamins from a nutrition store, you’ll probably notice a best-by date on the bottom of the jar. But that inscribed number isn’t a hard-and-fast rule—there is some ...
3. Opened Puzzles. Buying opened puzzles at a thrift store is a gamble you probably don’t want to take. Even if it looks complete, there’s no guarantee all the pieces are actually there.
Pay attention to how long you've been outside and go back inside before those symptoms above start to creep up. Keep your cellphone with you in case there's an emergency. Wear reflective clothing ...
The CsFr molecule is predicted to have francium at the negative end of the dipole, unlike all known heterodiatomic alkali metal molecules. Francium superoxide (FrO 2) is expected to have a more covalent character than its lighter congeners; this is attributed to the 6p electrons in francium being more involved in the francium–oxygen bonding. [4]