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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 alkali metals (lithium, sodium, potassium, rubidium, caesium, and francium) are the most homogeneous column of elements in the periodic table, exhibiting very clear periodic trends. All of them are soft and extremely reactive metals, readily giving up their sole valence electron to form cations.
The most reactive metals, such as sodium, will react with cold water to produce hydrogen and the metal hydroxide: 2 Na (s) + 2 H 2 O (l) →2 NaOH (aq) + H 2 (g) Metals in the middle of the reactivity series, such as iron , will react with acids such as sulfuric acid (but not water at normal temperatures) to give hydrogen and a metal salt ...
As a result, element 173 is expected to behave chemically like an alkali metal, and one that might be far more reactive than even caesium (francium and element 119 being less reactive than caesium due to relativistic effects): [90] [19] the calculated ionisation energy for element 173 is 3.070 eV, [91] compared to the experimentally known 3.894 ...
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.
Thallium is a soft, reactive metal (MH 1.0), so much so that it has no structural uses. [114] It has a close-packed crystalline structure (BCN 6+6) but an abnormally large interatomic distance that has been attributed to partial ionisation of the thallium atoms. [ 115 ]
francium: 87: 1b: Due to its very short half-life, there is almost no potential for a living thing to be exposed to it. Even synthesis cannot produce more than minute quantities before it decays, so there is no medical use. [11] Radioactive. [11] gadolinium: 64: 2ac: Has no known function in humans, and is not taken up by plants. [11]