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  • Francium - Wikipedia
    Francium is a chemical element; it has symbol Fr and atomic number 87 It is extremely radioactive; its most stable isotope, francium-223 (originally called actinium K after the natural decay chain in which it appears), has a half-life of only 22 minutes
  • Francium | Radioactive, Alkali Metal, Rare | Britannica
    francium (Fr), heaviest chemical element of Group 1 (Ia) in the periodic table, the alkali metal group It exists only in short-lived radioactive forms Natural francium cannot be isolated in visible, weighable amounts, for only 24 5 grams (0 86 ounce) occur at any time in the entire crust of Earth
  • Francium: Facts about the elusive radioactive element
    Francium — the 87th element on the periodic table — is a naturally occurring, but incredibly rare, radioactive element It forms and decays extremely quickly, so it has no practical uses, and it
  • Francium Facts, Symbol, Discovery, Properties, Uses - Chemistry Learner
    Francium definition, discovery, properties (atomic mass, color, melting point, atomic number, electron configuration), reactivity in water, common uses
  • Francium - Element information, properties and uses | Periodic Table
    Element Francium (Fr), Group 1, Atomic Number 87, s-block, Mass [223] Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images
  • Francium (Fr) – Definition, Preparation, Properties, Uses . . . - Examples
    Francium is a chemical element with significant scientific intrigue, primarily due to its rarity and position in the periodic table As the heaviest known alkali metal, Francium exhibits unique properties that captivate chemists and educators
  • Francium Facts (Atomic Number 87 or Fr) - ThoughtCo
    Francium is a rare and highly unstable element with the atomic number 87 and symbol Fr Discovered in 1939, francium decays quickly, making it the second rarest natural element after astatine Due to its rarity and instability, francium is mainly used for research, including spectroscopic experiments
  • Francium Element Facts - chemicool. com
    Francium is a heavy, unstable, radioactive metal with a maximum half-life of only 22 minutes It has a low melting point (27 o C, 81 o F) and, if enough of it could be accumulated, it would be liquid in a warm room Francium is the second rarest element in the Earth’s crust, next to astatine
  • Periodic Table of Elements: Los Alamos National Laboratory
    Francium, the heaviest known member of the alkali metals series, occurs as a result of an alpha disintegration of actinium It can also be made artificially by bombarding thorium with protons While it occurs naturally in uranium minerals, there is probably less than an ounce of francium at any time in the total crust of the earth
  • Meet Francium - The Element So Radioactive That It Hardly Exists
    For many years, the very existence of francium was a matter of conjecture It was Dmitri Mendeleev - the father of the periodic table - who first theorized that there might be an undiscovered





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