Francium - Wikipedia
网页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. [4]
Francium - Element information, properties and uses ...
网页Element Francium (Fr), Group 1, Atomic Number 87, s-block, Mass [223]. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images.
Francium | Radioactive, Alkali Metal, Rare | Britannica
网页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. The existence of francium was predicted by ...
Francium Facts (Atomic Number 87 or Fr) - ThoughtCo
网页2019年11月4日 · Francium is a highly radioactive alkali metal with the atomic number 87 and element symbol Fr. Although it occurs naturally, it decays so quickly it's very rare. In fact, scientists have never had a large enough sample of francium to know what it …
Francium: Facts about the elusive radioactive element | Live ...
网页2022年7月26日 · 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...
Francium: Element 87 - Properties, History, and Uses
网页Francium is a highly radioactive element with the atomic number 87, belonging to the alkali metal group in the periodic table. Its general importance is more academic and research-based than practical due to its scarcity and high instability.
Francium | History, Uses, Facts, Physical & Chemical ...
网页Francium is the shiny metal in its pure state and exist in liquid form at room temperature rather than a solid. Francium belongs to alkali group of the periodic table so its physical properties are similar with alkali group elements.