All isotopes of francium decay into astatine, radium, or radon. Francium is an alkali metal whose chemical properties mostly resemble those of caesium. The isotopes of francium decay quickly into astatine, radium, and radon. Four more elements have melting points slightly above room temperature&colon; francium, caesium, gallium and rubidium. Thus, contrary to expectation, caesium is the most reactive of the alkali metals, not francium. Francium (Fr) has no stable isotopes. There are 34 known isotopes of francium ranging in atomic mass from 199 to 232. Some of these nuclides are very short-lived, such as [[isotopes of francium]]. The sixth alkali metal is now considered to be francium. Francium and radium make up the s-block elements of the 7th period. Nearly all francium salts are water-soluble. Francium has not been synthesized in amounts large enough to weigh. Due to its instability and rarity, there are no commercial applications for francium. Perey then suggested "francium", after France. Finally, Sam Kean talks about francium, "magic elements" and the future of the periodic table.