from The American Heritage® Dictionary of the English Language, 4th Edition
- n. An extremely unstable radioactive element of the alkali metals, produced artificially from actinium or thorium, having approximately 19 isotopes, the most stable of which is Fr 223 with a half-life of 21 minutes. Atomic number 87; valence 1. See Table at element.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A metallic chemical element (symbol Fr) with an atomic number of 87.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a radioactive element of the alkali-metal group discovered as a disintegration product of actinium
Some of the elements, such as francium and californium, were named to honor the places where they were discovered.
Per Wikipedia: Mercury is a heavy, silvery d-block metal [that] is one of six elements that are liquid at or near room temperature and pressure, the others being caesium, francium, gallium, bromine, and rubidium.
Only 20 atoms of francium exist at any given instant.
There are some very unstable radioactive elements, like francium, that last just a couple of minutes and then decay.
And phosphorus and francium and fluorine and terbium,
Lindsay's about as unstable right now as the element francium.
7: Nice touch of science, but it'd have to be a pretty high room temperature for cesium, francium, gallium and rubidium to melt--the lowest melting point among them is francium's 300 degrees Kelvin, which is 80.6 degrees Fahrenheit.
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