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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]
There are techinically a few pictures of francium floating around, 2 of which are on the element's article (the 300,000 atom heat one and the 200,000 atom light one), and 2 here (the black and white one of 1000 atoms, and the discovery paper). However, none of these depict the atom directly, they are just images of the heat and light emitted by ...
The remaining elements of the group (scandium, yttrium, lutetium) are quite electropositive. They are reactive metals, although this is not obvious due to the formation of a stable oxide layer which prevents further reactions. The metals burn easily to give the oxides, [53] which are white high-melting solids. They are usually oxidized to the ...
The stabilisation of ununennium's valence electron and thus the contraction of the 8s orbital cause its atomic radius to be lowered to 240 pm, [36]: 1729–1730 very close to that of rubidium (247 pm), [5] so that the chemistry of ununennium in the +1 oxidation state should be more similar to the chemistry of rubidium than to that of francium.
Why is francium so unstable? The article doesn't explain. Google found me a Prezi presentation (), but first off that's not a reliable source for expanding the francium article, and secondly it doesn't explain why many isotopes of related elements, e.g. 238 U with 54 more neutrons than protons, are so much longer lived.
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 ...
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]
If sodium is to be placed above potassium then what about ceasium and francium?182.55.242.11 14:17, 9 July 2011 (UTC) K is indeed more reactive than Na, which is indeed more reactive than Li. This can be proven with a simple experiment in which you drop a small piece of each metal into separate beakers of water.