Francium

__Francium__ Francium is a chemical element with symbol Fr and atomic number 87. This is a highly radioactive metal that decays into astatine, radium and radon. Francium has highest equivalent weight of any element.

Francium was discovered in 1939 in France by Marguerite Derey.(hence the name Francium). This was the last element discovered in nature, rather than by synthesis. It naturally occurs in Uranium Minerals.

Francium is extremely rare outside of the laboratory and due to its rarity there are no commercial applications for this element.

Francium is classified as an "Alkali Metal."

Radioactive Francium was discovered by Marguerite Catherine Perey, a French chemist, in 1939 while analyzing actinium's decay sequence. Although considered a natural element, scientists estimate that there is no more than one ounce of francium in the earth's crust at one time. Since there is so little naturally occurring francium on earth, scientists must produce francium in order to study it. Francium can be produced by bombarding thorium with protons or by bombarding radium with neutrons. Francium's most stable isotope, francium-223, has a halflife of about 22 minutes. It decays into radium-223 through beta decay or into astatine-219 through alpha decay. Due to the small amounts produced and its short half-life, there are currently no uses for francium outside of basic scientific research.
 * Atomic Number:** 87
 * Atomic Weight:** 223
 * Melting Point:** 300 K (27°C or 81°F)
 * Boiling Point:** Unknown
 * Density:** Unknown
 * Phase at Room Temperature:** Solid
 * Element Classification:** Metal
 * Period Number:** 7 **Group Number:** 1 **Group Name:** Alkali Metal
 * What's in a name?** Named for the country of France.
 * Say what?** Francium is pronounced as **FRAN-see-em**.
 * History and Uses:**
 * Estimated Crustal Abundance:** No Data Available
 * Estimated Oceanic Abundance:** No Data Available
 * Number of Stable Isotopes:** 0 (View all isotope data)
 * Ionization Energy:** 3.9 eV
 * Oxidation State:** +1


 * Symbol:** Fr **Atomic Number:** 87 **Atomic Mass:** (223.0) amu **Melting Point:** 27.0 °C (300.15 K, 80.6 °F) **Boiling Point:** 677.0 °C (950.15 K, 1250.6 °F) **Number of Protons/Electrons:** 87 **Number of Neutrons:** 136 **Classification:** Alkali Metal **Crystal Structure:** Cubic **Density @ 293 K:** Unknown **Color:** Unknown

Atomic Structure

 * [[image:http://www.chemicalelements.com/bohr/b0087.gif width="383" height="381"]] ||  || **Number of Energy Levels:** 7
 * First Energy Level:** **Second Energy Level:** **Third Energy Level:** **Fourth Energy Level:** **Fifth Energy Level:** **Sixth Energy Level:** **Seventh Energy Level:** ||

Isotopes

 * ** Isotope ** || ** Half Life ** ||
 * Fr-212 || 20.0 minutes ||
 * Fr-221 || 4.8 minutes ||
 * Fr-222 || 14.3 minutes ||
 * Fr-223 || 21.8 minutes ||

Facts

 * Date of Discovery:** 1939 **Discoverer:** Marguerite Derey **Name Origin:** After France **Uses:** No uses known **Obtained From:** decay of actinium

Who identified francium? Francium was identified by Marguerite Perey, working at the Curie Institute in Paris, in 1939. Marguerite Perry and been Marie Curie’s assistant and she carried on the work of analysis of the radio active ore, pitchblende, after Marie Curie’s death. Francium was identified from the radio active decay of actinium. About francium: Francium has a very short half life of around 20 minutes. For this reason it is very rare in the Earth’s crust (probably around 10 grammes at any given time!). The francium that does exist is found in trace amounts in uranium ores. Francium metal has never been seen with the naked eye. It is formed from the radio active decay of actinium. || ||
 * [[image:http://chem103csu.wikispaces.com/site/embedthumbnail/placeholder?w=340&h=321 width="340" height="321"]] || Francium atom ||
 * Francium is a radio active element that is found in trace amounts in uranium ores, such as pitchblende. ||   ||   ||
 * What the name means: Francium was named after France, the country where it was first identified.