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 is formed by radioactive decay of actinium, and artificially made by bombarding thorium with protons. It is naturally present in uranium and consider the second rarest element in the earth crust. It exists in short-lived radioactive forms and cannot be isolated in pure stable form.

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), 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 …

2018年3月2日 · Francium (pronounced as FRAN-see-em) is an alkali metal denoted by the symbol, Fr. No more than 15 grams of the element is found in the earth’s crust [1, 5]. Its most stable isotope is Francium-223 having a half-life of 22 minutes that either undergo beta decay or alpha decay to form radium-223 and astatine-219, respectively [3].

2020年11月21日 · Francium is a 87. chemical element in the periodic table of elements. It has 87 protons and 87 electrons in the atomic structure. The chemical symbol for Francium is Fr.

Francium is the 87th element in the periodic table and has a symbol of Fr and atomic number of 87. It has an atomic weight of (223) and a mass number of 197. Francium has eighty-seven protons and one hundred ten neutrons in its nucleus, and eighty-seven electrons in seven shells.

Francium is a chemical element of the periodic table with chemical symbol Fr and atomic number 87 with an atomic weight of 223 u and is classed as alkali metal and is part of group 1 (alkali metal). Francium is solid at room temperature.

Francium - Properties, history, name origin, facts, applications, isotopes, electronic configuation, crystal structure, hazards and more; Interactive periodic table of the chemical elements.

With 87 protons the new element belonged in Group 1 of the periodic table, joining the other five alkali metals: lithium, sodium, potassium, rubidium and cesium. The discovery of francium completed humankind’s discoveries of naturally occurring elements.