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. Francium is a chemical element with symbol Fr and atomic number 87. Classified as an alkali metal, Francium is a solid at room temperature.

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10月22日 · Francium is a radioactive element with atomic number 87 and element symbol Fr. While this alkali metal occurs naturally, it’s very rare. It’s also highly reactive and unstable, so it’s not an element you’ll encounter in daily life.

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 is a chemical element with symbol Fr and atomic number 87. It used to be known as eka-caesium and actinium K. It is the second-least electronegative element, behind only caesium. Francium is a highly radioactive metal that decays into astatine, radium, and radon.