When Mendeleev first proposed his periodic table in 1869 he left gaps for elements not yet discovered, but that he predicted should exist. One such gap was one beneath caesium, a position later found ...

Gethin: Francium. That's not an element that you ... Non-metal elements are on the right of the periodic table. Metal elements are found on the left and in the middle of the table.

Note that older texts list both francium and cesium as least electronegative ... electronegative elements are found on the top right of the periodic table, while the least electronegative elements are ...

It was recognized early on that the periodic table more or less fizzles ... As it turns out, francium was one of the last natural elements to be discovered, and is the second rarest after astatine.

You may use table navigation commands for the screen reader of your choice. The Periodic Table of Elements. Each entry contains the atomic number, chemical symbol, and atomic mass to two decimal ...